Prasanna

Detailed explanations in West Bengal Board Class 10 Geography Book Solutions Chapter 5.6 Natural Vegetation of India offer valuable context and analysis.

WBBSE Class 10 Geography Chapter 5.6 Question Answer – Natural Vegetation of India

Answer in short : 2 Marks

Question 1.
Where wet deciduous forests are found in India ?
Answer:
Lower slopes of the Himalayas, Assam, West Bengal, Bihar, Jharkhand, Odisha, Madhya Pradesh, Maharashtra, Karnataka and the adjoining regions.

Question 2.
Mention the climatic conditions where dry deciduous forests grow.
Answer:
Dry deciduous forests are mostly found in areas having a mean annual temperature of 23°-27° C, an annual rainfall for 50-100 cm and humidity ranging from 51% to 58%.

Question 3.
Where tidal forests are found in India ?
Answer:
In India, Mangrove forests are found in Sundarbans (WB), the Mahanadi delta, Godavari delta, Krishna delta, Cauvery delta and the coasts of Andaman and Nicobar islands.

Question 4.
What is Social forestry?
Answer:
Social forestry is defined as ‘Forestry outside the conventional forests’. The barren or infertile lands near about villages are converted to forest lands after treating the soil. The villagers take care of the forest and plant trees of their choice, in order to meet their daily needs.

Question 5.
What is Agro-forestry?
Answer:
Agro-forestry is any sustainable land-use system that maintains or increases total yields by combining food crops with tree crops and livestock on the same land, either alternately or at the same time. This system is adopted for both ecological as well as economic benefits.

Question 6.
Name the major types of forest found in India.
Answer:
Major types of forest found in India are Tropical evergreen rain forests, Tropical deciduous forests [sub-divided into Dry deciduous and Wet deciduous], Semi desert and desert vegetation, Tidal or mangrove forests and Mountain forests.

Question 7.
What is a forest?
Answer:
Presence of a huge number of trees of different or same species in a particular area is known as a forest.

Question 8.
What is natural vegetation?
Answer:
Vegetation that grows with the help of natural entities like soil, water, sunlight, CO_2, without the interference of man, is known as natural vegetation.

Question 9.
Where are evergreen forests found in India ?
Answer:
Evergreen forests are found in India in :

1. Andaman and Nicobar islands.
2. Western slope of western ghats.
3. The north-eastern hilly region.
4. Terai-Duars region at the foothills of Himalaya.

Question 10.
Why have evergreen forests grown in the western slopes of the western ghats?
Answer:
The western slopes of the Western Ghats receive about 300-400 cm of rainfall from the Arabian Sea branch of the south-west monsoon. Thus this region is suitable for the growth of evergreen trees.

Question 11.
Why is there very little coniferous forests in India ?
Answer:
The main climatic condition needed for coniferous forests is long chilling winters and short cool summers. Only a few places in India enjoy this kind of a climate. Eg.- Uttarakhand, Himachal Pradesh, Jammu and Kashmir, Sikkim, Darjeeling district of West Bengal. Hence, amount of coniferous forests in India is quite less.

Question 12.
Why does Jammu possess dense forests while Ladakh is bare, even though both are situated in the same state?
Answer:
Jammu and Ladakh both lie in the state of Kashmir. Jammu lies in the windward slope of the Pir Panjal range. It receives enough rainfall and hence has dense forests. On the other hand, Ladakh lies in the leeward side and rainshadow area of the mountains. Hence, vegetative growth is very less here due to lack of rainfall.

Question 13.
Where do coniferous forests lie in India ?
Answer:
Coniferous forests are found in India in the Eastern Himalayas (3000-4000 m) as well as the Western Himalayas (2000-4000 m).

Question 14.
Name some coniferous trees.
Answer:
Pine, fir, deodar, spruce, laurel, willow, elm, silver fir, etc.

Question 15.
What is ‘Green gold’?
Answer:
The Himalayan mountains are covered with dense forests from 500-4000 m altitude. This region is a very important part of the environment as it houses numerous rare and important species of plants and huge biomass. Thus, this forest is known as the ‘Green gold’.

Question 16.
What do you mean by conservation of forests ?
Answer:
The process of scientific and rational utilisation of forests and forest products along with securing them for future use by the next generations is called conservation of forests.

Question 17.
What do you mean by ‘Forest Management’ ?
Answer:
Maintenance of forests by government’s forest workers, NGOs and the local people together for a common interest, is known as ‘Forest Management’.

Question 18.
Name some trees of the evergreen forests of the tropical regions.
Answer:
Mehogany, Chaplas, Sissoo, Garjan, Rubber, Rosewood, Iron wood, Ablus etc.

Question 19.
Name some trees of the Tropical wet deciduous forests.
Answer:
Sal, Teak, Mango, Peeple, Neem, Kendu, Khayer, Arjun, Siris, Sandal wood, Palash, Mahua etc.

Question 20.
Name some tropical desert plants.
Answer:
Babul, Khayer, Palm, Cactus, Acacia etc.

Question 21.
What are Alpine meadws?
Answer:
The long stretches of grasslands that grow in the Himalayas at an altitude of 3,500-5,000 m are called Alpine meadows. They grow in the region between the tree line and the permafrost region.

Answer in brief : 3 Marks

Question 1.
What are the characteristics of wet deciduous or monsoon type forests?
Answer:
The characteristics of monsoon type or wet deciduous forests are :
(i) The trees shed their leaves in the dry season and grow new leaves by the rainy season.
(ii) Majority of the trees are broad-leaved and yield hard-wood.

Question 2.
What are the characteristics of Dry deciduous forests or scrubs?
Answer:
The characteristics of Dry deciduous forests are :

1. These forests consist of stunted trees and bushes which are widely scattered.
2. They fade away into scrubs and thorny bushes that are typical of desert region.
3. Trees are only 6 to 10 m high.
4. They have long roots which enable them to obtain water from deep underground.

Question 3.
Describe the desert and semi-desert vegetation.
Answer:
(i) The type of vegetation is thorny shrubs and bushes. These are called Xerophytic plants and have adaptations to withstand drought.
(ii) Some short coarse grasses grow here and there, where conditions are more drought like.

Question 4.
Describe the growth of tidal forests.
Answer:
Tidal forests or mangroves flourish in tide washed coastal areas where mud and silt have accumulated. The trees have different adaptations to support them in the wet soil. Eg – stilt roots, prop roots, buttress roots. Some breathing roots also pop out of the soil to allow the roots to acquire oxygen from the air.

Question 5.
What kind of forests grow on mountainous regions above 1500 m height?
Answer:
On mountainous regions above 1500 m height, temperate conifer trees such as pine, fir, oak, maple, deodar, laurel, spruce and cedar grow. At the yet higher altitudes, plants like rhododendrons and junipers are found. Beyond these vegetation belts, alpine grasslands appear upto the permanent snowfields.

Question 6.
List the regions where Wet deciduous forests grow in India.
Answer:
The various areas where Wet deciduous forests grow in India are :

1. Terai-Duars region at the foothills of the Himalaya.
2. Eastern slope of the Western Ghats.
3. Chotanagpur plateau.
4. Plains of the Western coasts
5. Plains of Uttar Pradesh, Bihar, Odisha, Andhra Pradesh, Telengana. Karnataka and Kerala.

Question 7.
Name the areas where Dry deciduous forests grow in India.
Answer:
In India, Dry deciduous forests grow in :

1. Rain shadow area of the Western Ghats.
2. Highlands of Central India.
3. Eastern parts of Aravalli range.
4. Upper Ganga and Sutlej basins.
5. Several parts of the peninsular plateau.

Question 8.
List the regions where mangrove forest is found in India.
Answer:
In India, mangrove forest is found in :

1. Sundarban in the delta region of river Ganga.
2. Pimbavaram near Chidambaram of Tamil Nadu.
3. Bhitarkanika of Odisha in the Mahanadi delta.
4. Godavari and Krishna delta regions in Andhra Pradesh.
5. Cauvery delta region in Tamil Nadu.
6. Malabar coast of Kerala.
7. Kutch region of Gujarat.
8. Lower Luni valley of Rajasthan.
9. Khambat region of Gujarat.
10. Andaman and Nicobar islands.

Question 9.
Name the different trees found in different forests of the Himalayan region.
Answer:

Type of forest	Trees
i. Evergreen	Birch, maple, ash, chestnut, poplar, walnut, ablus, alder, chaplas, etc.
ii. Mixed deciduous	Sal, teak, sissoo, bamboo, cane, garjan, jarul, etc.
iii. Coniferous	Pine, fir, oak, birch, deodar, cedar, poplar, rhododendron, nuxvomica, magnolia, etc.
iv. Alpine	Grasslands and bushy trees like juniper, rhododendron, etc.

Question 10.
Where is desert vegetation found in India? Name the main species of trees.
Answer:
Desert vegetation is found in India in :

1. Thar desert region of Rajasthan.
2. Kutch and Kathiawar regions of Gujarat.
3. Deserted or arid regions of South Punjab.

The main species of trees are-khayer, babul, date palm, cactus, different kinds of grasses and bushy plants, etc.

Answer in details : 5 Marks

Question 1.
Describe briefly the forests of India.
Answer:
Forests in India can be broadly classified as follows:
i. Tropical Evergreen rainforests : These forests grow in regions of temperature 25°-27° C and rainfall 200-300 cm. These are very dense forests with tall broad leaved trees, and thick undergrowth. These forests are difficult to exploit for commercial purposes. Main species are – rosewood, iron wood, champa, gurjan chaplas etc. They are found in the windward slopes of western ghats, hilly regions of north-east India, West Bengal and Odisha.

ii. Tropical deciduous forests :
(a) Wet deciduous or monsoon type forests : This grows in regions of temperature 26°-27° C, rainfall 100-200 cm and humidity 60-80%. Majority of trees are broad-leaved and yield valuable hard wood. They shed their leaves in the dry season. Main species are teak, sal, sandalwood, deodar, bluegum, ebony, sisam, palash, arjun etc. They are found in the lower slopes of the Himalayas, Assam, West Bengal, Bihar, Jharkhand, Odisha, Madhya Pradesh, Maharashtra, Karnataka and adjoining areas.

(b) Dry deciduous forests : They are found in regions having temperature of 23°-27° C, rainfall 50-100 cm and humidity 51%-58%. These forests consist of stunted trees (6 to 10 m) and bushes that fade away into scrubs and thorny bushes. They have long roots that draw water from deep underground. Main species are – babul, wild palm, acacia etc.

iii. Semi desert and desert vegetation : These vegetations grow in very hot and arid regions with rainfall less than 50 cm. The trees are mostly thorny shrubs that can withstand drought. Some short coarse grass are also found. Main species are – cactus, babul, acacia etc. They are mostly found in Rajasthan, parts of Gujarat, Punjab etc.

iv. Tidal forests : They grow on the tide washed coastal plains where there is accumulation of mud and silt. They are also called Mangroves. They have supporting as well as breathing roots to help them survive in the soft moist and saline soil. Main species are sundari, keora, garan, hetal, hogla etc. They are found in the Sundarbans (WB) and deltas of rivers Mahanadi, Godavari, Krishna and Cauvery and along the coast of Andaman and Nicobar islands.

v. Mountain forests : Mountain forests vary according to altitude (a) On the foothills of Himalayas upto 1500 m, evergreen trees such as sal, teak, bamboo and cane grow abundantly.

(b) On higher slopes of 1500 m-3500 m, temperature conifer trees like pine, fir, oak, maple, deodar, laurel, spruce, cedar etc grow. At higher altitudes, rhododendrons and junipers are found. Beyond this, the alpine grasslands appear and fade away near the permanent snow fields.

Question 2.
List the different uses of forests.
Answer:
The different uses of forests are :

1. Forests help to maintain the ecological balance of the earth.
2. Forests are the houses of numerous species of plants, animals, insects, birds etc.
3. The trees provide wood for various construction, industrial and domestic purposes.
4. They provide raw materials for paper, matchstick, cardboard, furniture and other industries.
5. Apart from wood, forests also provide with useful items like leaves, roots, gums, raisins, nuts, fruits etc.
6. Forests provide employment to many people directly and indirectly.

Question 3.
What is Forest Conservation ? What is its need ?
Answer:
‘Forest Conservation’ refers to the proper and need based utilisation of forests without hampering the environment and the species of plants and animals residing there. The needs for Forest conservation are :

1. To reduce soil erosion
2. To control floods and droughts
3. To control spread of deserts
4. To control global warming
5. To maintain the ecologial balance.
6. To conserve the species of plants and animals and prevent their extinction.

Question 4.
What methods can be taken up for Forest Conservation ?
Answer:
The different methods that can be taken up for forest conservation are :

1. Afforestation or re-planting of trees after deforestation, especially on hill slopes.
2. Prevention of felling of immature trees.
3. Converting forests into Reserve Forests in order to preserve flora and fauna.
4. Controlled grazing of animals on grasslands so that small and young plants and new grass are not hampered.
5. Protection from forest fires by removing dry branches and leaves.
6. Use of substitute fuel other than wood.
7. Use of modern equipments in felling of trees, so that other trees are not hampered.
8. Enactment of laws to prevent indiscriminate felling of trees.
9. Taking up programmes like ‘Van Mahotsav’ and planting of new saplings.
10. Increasing public consciousness.
11. Proper utilisation of forest resources without westage.

Question 5.
Differentiate between Social forestry and Agro-forestry.
Answer:

Social forestry	Agro-forestry
i. Barren and discarded land beyond the forested areas are taken care of by NGOs, voluntary organisations and local people to plant trees and grow a new forest.	i. Barren or infertile lands belonging to farmers are taken care of to grow trees for wood, green manure medicinal plants, fruits etc.
ii. Creation of new forests help to control soil erosion, maintain ecological balance, reclaim infertile land, supply useful forest products etc.	ii. Use of barren and infertile land belonging to farmers help in making the land economically fruitful. It also increases soil fertility, supplies important daily needs, prevents soil erosion, meets demand for fire wood, supplies fodder for animals etc.
iii. Such forests are grown in discarded lands beside agricultural plots, along railway lines and roadways, along river valleys, in religious places, schools, offices, etc. in burial grounds, crematories etc.	iii. Such forests are grown in the lands belonging to the farmers themselves, which have become infertile and unproductive.
iv. It is a co-operative and joint venture of NGOs, voluntary organisations and local people.	iv. It is generally a personal or social venture.
v. Available products are fruits, roots, fire wood, animal fodder, honey, wax, lax etc.	v. Available products are fire wood, wood for furniture, green manure, medicines, fruits etc.

Question 6.
Describe the characteristics of the evergreen forests.
Answer:
The characteristics of the evergreen forests are :

1. The trees do not shed their leaves altogether in one season. Hence the forest appears evergreen.
2. The forest is very dense.
3. The trees are very tall and highly branched.
4. The leaves of the trees are broad, thick and dark green in colour.
5. The trees occur in different layers in the forest, starting from tall trees to creepers.
6. The leaves create a canopy over the head of the forest and allow very little light to penetrate the forest.
7. The forest is moist and dingy. It holds the highest variety of flora and fauna.

Question 7.
Describe the characteristics of Wet deciduous forests.
Answer:
The characteristics of wet deciduous forests are :

1. The trees shed their leaves altogether in the dry season. Hence they are called deciduous.
2. The woods acquired from the deciduous trees are hard and highly valuable.
3. Most of the trees have straight trunks that are smooth and plain. But some trees may have rough surface of trunks.
4. The trees are highly branched.
5. Age rings are prominent in the trunks of the trees.

Question 8.
Describe the characteristics of Dry deciduous forests.
Answer:
The characteristics of dry deciduous forests are :

1. The main type of Vegetation found here is grasslands.
2. The trees are of short height (6-10 m tall).
3. The trees shed their leaves in the dry season.
4. The forest is bushy.
5. The forest is not dense and the trees are distributed haphazardly here and there.
6. These forests are known as Savannah forests of the Deccan plateau region of India due to predominance of grasslands.
7. The wood collected is mostly used as fire wood.
8. Sabai grass found here is used for making paper.
9. Leaves of several plants have much economic importances. Ex- Kendu leaves are used to make ‘biris’. Sal leaves are used to make plates and bowls.
10. Different kinds of raisins and gums are acquired from these forests.

Question 9.
What are the characteristics of desert vegetation of the tropical region?
Answer:
The charackeristics of tropical desert vegetation are :

1. The trees are provided with thorns and the leaves are usually very small.
2. The roots are very long in order to collect water from deep down into the soil.
3. Most of the trees have juicy stems and contain chlorophyll.
4. Average height of the trees is 6-10 m. They are mostly bushy in nature.
5. Most of the trees have leaves and branches covered or coated with cuticle, so as to prevent excess loss of water through transpiration.

Question 10.
Discuss about the mangrove forests found in India.
Answer:
Mangrove forests exist in the hot tropical and sub-tropical climatic regions along the coastal regions. The regions which receive 150 cm of rainfall and 26°-28° C temperature and are influenced by tides twice a day are most suitable for the growth of mangrove forests.
Characteristics :

1. The soil remains moist due to tidal action. Hence the trees are evergreen.
2. The trees grow several supporting roots like stilt roots, prop roots and buttress roots to hold them upright in the soft, moist soil.
3. The trees are also provided with breathing roots that pop out of the soil to trap oxygen directly from the air.
4. The trunks are juicy and are highly branched.
5. The trees are medium tall, woody and sometimes bushy.

Question 11.
Discuss the influence of climate on the natural vegetation in India.
Answer:
Climate plays the most important role in creating the natural vegetation of a region. The distribution of natural vegetation in India according to climatic conditions is discussed below :
i. High temperature and high rainfall : Evergreen forests grow in regions of temperature 20°-30° C and average rainfall of 200 cm. The regions of such forests are- (i) North eastern hilly region, (ii) Terai-Duars region of the foot hills of Himalaya, (iii) Andaman and Nicobar islands. (iv) Western slopes of Western Ghats.
Main species : Sissoo, Garjan, Rosewood, Mehogani, Chaplas, Iron Wood, Bamboo, Rubber, etc.

ii. High temperature and moderate rainfall: The regions having average temperature of 20°-30° C and average rainfall of 100-200 cm have deciduous types of forests. Regions : (i) Eastern slopes of Western Ghats, (ii) Madhya Pradesh, (iii) Jharkhand, (iv) Chattisgarh, (v) Uttar Pradesh, (vi) Odisha etc. Main species : Sal, Shimul, Teak, Mahua, Palash, Banyan, Peepal, etc.

iii. High temperature and low rainfall : The regions having average temperature of 25°-30° C and average rainfall 50-100 cm have grassland type of vegetation with short and bushy trees. Regions : (i) eastern parts of Rajasthan, (ii) Kutch and Kathiawar regions of Gujarat, (iii) Rain shadow areas of the Westen ghats. Main species : Sabai grass, other bushy trees.

iv. High temperature and very low rainfall : The region having average temperature around 40° C and average rainfall below 50 cm have desert type of vegetation with scarce distribution of thorny bushes.
Region : This kind of vegetation is seen in the Marusthali region of Rajasthan. Main species : Babul, Acacia, Cactus, etc.

v. Difference in rainfall according to altitude : In the mountainous region of the Himalayas, temperature goes on decreasing with increase in altitude. Also, distribution of rainfall varies with altitude. The series of forests thus developed from lower to higher altitudes are – Evergreen forests, Deciduous forests, Coniferous forests and Alpine forests till the treeline is reached.

Multiple Choice Questions (MCQ) : 1 Mark

Question 1.
The minimum forest cover necessary to maintain ecological balance is
(A) 50% of the total land area
(B) 40% of the total land area
(C) 33% of the total land area
(D) 25% of the total land area
Answer:
(C) 33% of the total land area

Question 2.
Which state in India has the largest area under forests ?
(A) Himachal Pradesh
(B) Madhya Pradesh
(C) Karnataka
(D) Assam
Answer:
(B) Madhya Pradesh

Question 3.
How much area of the country is under forest :
(A) 23 per cent
(B) 25 per cent
(C) 30 per cent
(D) 40 per cent
Answer:
(A) 23 per cent

Question 4.
Coniferous forests in India are :
(A) 3 per cent
(B) 5 per cent
(C) 7 per cent
(D) None of these
Answer:
(A) 3 per cent

Question 5.
Coniferous forests in India are found in :
(A) The Himalayas
(B) The Nilgiri Hills
(C) Annamalai Hills
(D) Western Ghats
Answer:
(A) The Himalayas

Question 6.
Broad leaf forests in India are :
(A) 75 per cent
(B) 97 per cent
(C) 90 per cent
(D) 80 per cent
Answer:
(B) 97 per cent

Question 7.
Largest non-reporting area in India is in
(A) Jammu and Kashmir
(B) Nagaland
(C) Arunachal Pradesh
(D) Mizoram
Answer:
(A) Jammu and Kashmir

Question 8.
Of the total reporting area in the India the area under forests consitutes
(A) 21.6%
(B) 12.8%
(C) 10.7%
(D) 43.2%
Answer:
(A) 21.6%

Question 9.
The name of mangrove forest of the Ganga delta is
(A) Bhitarkanika
(B) Cudappa forest
(C) Sundarban
(D) Bharatnagar
Answer:
(C) Sundarban

Question 10.
Sundarban in West Bengal is the habitat of
(A) The tiger
(B) The elephant
(C) The lion
(D) The deer
Answer:
(A) The tiger

Question 11.
Kaziranga National Park is in
(A) Bihar
(B) Uttar Pradesh
(C) Assam
(D) Manipur
Answer:
(C) Assam

Question 12.
Tropical Deciduous forests are found in areas of rainfall per year.
(A) 25 to 50 cm
(B) 50 to 100 cm
(C) 100 to 200 cm
(D) More than 200 cm
Answer:
(C) 100 to 200 cm

Question 13.
Lowland grasses occur in the plains of
(A) Punjab
(B) Maharashtra
(C) Tamil Nadu
(D) Madhya Pradesh
Answer:
(A) Punjab

Question 14.
The ‘Nilgiri and Annamalai Hills’ have got :
(A) Tropical type of Vegetation
(B) Deciduous forests
(C) Coniferous forests
(D) Evergreen forests
Answer:
(D) Evergreen forests

Question 15.
In India about _____ of the total land area is under forests.
(A) 50%
(B) 27%
(C) 22.3%
(D) 29%
Answer:
(C) 22.3%

Question 16.
The object of ‘Van Mahotsava’ in India is the____
(A) Cultivation of a large belt of trees
(B) To worship the trees
(C) To show reverence to the trees
(D) To stop felling the trees
Answer:
(A) Cultivation of a large belt of trees

Question 17.
________ is an evergreen tree
(A) Sissoo
(B) Teak
(C) Palash
(D) None of these
Answer:
(A) Sissoo

Question 18.
________ trees grow over the chotanagpur plateau
(A) Deciduous
(B) Evergreen
(C) Coniferous
(D) Alpine
Answer:
(A) Deciduous

Question 19.
Mangrove trees are found in the
(A) Deltas
(B) Deserts
(C) Plains
(D) Mountain
Answer:
(A) Deltas

Question 20.
In the Evergreen Forests, rainfall should be
(A) Scanty
(B) Heavy
(C) Moderate
(D) Altogether sparse
Answer:
(B) Heavy

Question 21.
Forest is a resource.
(A) Non renewable
(B) Renewable
(C)Fund
(D) Flow
Answer:
(B) Renewable

Question 22.
The lowest forest cover is seen in
(A) Asia
(B) Africa
(C) North America
(D) South America
Answer:
(A) Asia

Question 23.
The Bhitarkanika forest in Odisha is famous for
(A) Equatorial trees
(B) Coniferous trees
(C) Dry deciduous trees
(D) Mangrove trees
Answer:
(D) Mangrove trees

Question 24.
The state of India under largest forest cover is
(A) Madhya Pradesh
(B) Chattisgarh
(C) Andhra Pradesh
(D) West Bengal
Answer:
(A) Madhya Pradesh

Question 25.
Highest percentage of forest is seen in
(A) Manipur
(B) Sikkim
(C) Nagaland
(D) Arunachal Pradesh
Answer:
(B) Sikkim

Question 26.
Forest is a __________ resource.
(A) Social
(B) Personal
(C) National
(D) International
Answer:
(C) National

Question 27.
Mangrove forests are seen in
(A) Polar regions
(B) Desert regions
(C) Hilly regions
(D) Coastal regions
Answer:
(D) Coastal regions

Question 28.
__________ is called a natural sponge.
(A) Marshlands
(B) Forests
(C) Deserts
(D) Ozone layer
Answer:
(B) Forests

Question 29.
Type of forests found in saline soil is
(A) Mangrove
(B) Tundra
(C) Mediterranean
(D) Coniferous
Answer:
(A) Mangrove

Question 30.
Most of India’s forest cover is
(A) Evergreen
(B) Deciduous
(C) Bushy
(D) Coniferous
Answer:
(B) Deciduous

Question 31.
Gewa trees belong to
(A) Mangroves
(B) Deserts
(C) Deciduous forest
(D) Alpine forests
Answer:
(A) Mangroves

Question 32.
In India, the Forest Research Centre is in
(A) Dehradun
(B) Jodhpur
(C) Kolkata
(D) Indore
Answer:
(A) Dehradun

Question 33.
Type of forest found at the foothills of the Himalayas is
(A) Deciduous
(B) Evergreen
(C) Bushy
(D) Coniferous
Answer:
(B) Evergreen

Question 34.
Type of forest found in the rain shadow area of Western Ghats is
(A) Mangrove
(B) Coniferous
(C) Alpine
(D) Grasslands
Answer:
(D) Grasslands

Question 35.
In the Himalayan range, above 400 m altitude lies the
(A) Coniferous forest
(B) Alpine forest
(C) Mangrove forest
(D) Evergreen forest
Answer:
(D) Evergreen forest

Question 36.
In the Himalayan range, above 3000-4000 m lies the
(A) Deciduous forest
(B) Coniferous forest
(C) Alpine forest
(D) Mangrove forest
Answer:
(B) Coniferous forest

Question 37.
Type of Vegetation found in Andaman and Nicobar islands is
(A) Evergreen
(B) Deciduous
(C) Cactus
(D) Coniferous
Answer:
(A) Evergreen

Question 38.
Natural vegetation is mostly controlled by
(A) Relief
(B) Soil
(C) River
(D) Climate
Answer:
(D) Climate

Question 39.
An example of a coniferous tree is
(A) Pine
(B) Ebony
(C) Garan
(D) Sal
Answer:
(A) Pine

Question 40.
Wet deciduous forest is seen in an area of rainfall
(A) 200 cm
(B) 100-200 cm
(C) 50-100 cm
(D) 25-50 cm
Answer:
(B) 100-200 cm

Question 41.
The vegetation found in deserts is
(A) Halophytes
(B) Cactus
(C) Deciduous
(D) Evergreen
Answer:
(B) Cactus

Question 42.
Mangrove forests grow in Sundarbans due to
(A) Laterite soil
(B) Black soil
(C) Saline soil
(D) Red soil
Answer:
(C) Saline soil

Question 43.
Vegetation found in the chotanagpur plateau region is
(A) Evergreen
(B) Deciduous
(C) Coniferous
(D) Desert Type
Answer:
(D) Desert Type

Question 44.
The north eastern hilly region is covered with
(A) Evergreen forests
(B) Deciduous forests
(C) Alpine forests
(D) Mangrove forests
Answer:
(A) Evergreen forests

Question 45.
The type of forest found in the plateau region of West Bengal is
(A) Evergreen
(B) Dry deciduous
(C) Mangrove
(D) Wet deciduous
Answer:
(B) Dry deciduous

State True or False : 1 Mark

1. Champa, toon, garjan, etc. trees are mostly found in West Bengal and Assam. [ ]
2. Selva-type of vegetation is found in Orissa. [ ]
3. The largest reserve of Sal is found in the forests of the peninsular India. [ ]
4. Acacia, Euphorbia and Tamarix plants are caracteristic of hill forests. [ ]
5. The natural vegetation in the Deccan plateau is mainly controlled by rainfall. [ ]
6. Blood-worts are mostly found in western Himalayas. [ ]
7. The tropical plants which need continuous high temperature for growth are called microtherms. [ ]
8. Tamarix is a common plant of deciduous forests. [ ]
Answer:
1. True
2. False
3. False
4.False
5. True
6. True
7. False
8. False

Match the following :

List I	List II
A. Tropical evergreen forest	1. Andaman Island
B. Monsoon forest	2. Mizoram
C. Dry Savanna	3. South-West Andhra Pradesh
D. Mangrove	4. Sahyadris

Answer:

List I	List II
A. Tropical evergreen forest	2. Mizoram
B. Monsoon forest	4. Sahyadris
C. Dry Savanna	3. South-West Andhra Pradesh
D. Mangrove	1. Andaman Island

Answer in few words : 1 Mark

Question 1.
What do you mean by natural vegetation?
Answer:
Vegetation that grows with the help of soil, water, sunlight and other physical environment, without the interference of man.

Question 2.
Name some evergreen trees.
Answer:
Rosewood, champa, gurjan, chaplas, sissoo, iron wood, etc.

Question 3.
Mention the required rainfall and temperature levels for wet deciduous forests.
Answer:
Temperature 26°-27° C, rainfall 100-200 cm.

Question 4.
What are the main trees of wet deciduous forests ?
Answer:
Teak, sal, sandalwood, deodar, sisam, jackfruit, mahua, palash, arjun, bamboo etc.

Question 5.
Where are dry deciduous forests found in India ?
Answer:
Central deccan plateau, south-east of Rajasthan, Punjab, Haryana, Parts of Uttar Pradesh, Madhya Pradesh.

Question 6.
What is the other name of Tidal forests ?
Answer:
Mangrove forests or Littoral forests.

Question 7.
Name some mangrove trees.
Answer:
Sundari, keora, goran, gewa, hogla, golpata, etc.

Question 8.
Where is semi-desert vegetation found in India ?
Answer:
Rajasthan, parts of Gujarat, Punjab, Karnataka.

Question 9.
Which factors influences natural vegetation the most?
Answer:
Climate.

Question 10.
What is the name of the process where man plants trees to build a forest?
Answer:
Afforestation.

Question 11.
In which year was the National Forest Policy of India taken ?
Answer:
1952.

Question 12.
How much portion of India’s total forest cover lies in West Bengal ?
Answer:
About 2.4%.

Question 13.
How tall does the bushy vegetation grow?
Answer:
Less than 3 m.

Question 14.
What kind of vegetation is found in the slopes of the Himalayan mountains?
Answer:
Coniferous forests.

Question 15.
Where is Alpine forest found in India ?
Answer:
Above 3000-5000 m altitude in the Himalayan range.

Question 16.
Name two mangrove forests of India.
Answer:
(i) Sundarban in West Bengal
(ii) Bhitarkanika in Odisha.

Question 17.
Name the first Reserved Forest of India.
Answer:
Jim Corbett National Park, Uttar Pradesh.

Question 18.
Why do halophytes need extra breathing roots ?
Answer:
The wet boggy soil does not allow them to breath within the soil.

Question 19.
To which direction will the forested zone of India shift due to global warming?
Answer:
Towards the north.

Question 20.
When was ‘Joint Forest Management’ started in India ?
Answer:
1989.

Question 21.
Why is the forest called a natural sponge?
Answer:
It absorbs CO₂ and releases O₂.

Question 22.
Which forest houses lions in India ?
Answer:
Gir forest of Gujarat.

Question 23.
How much land area of West Bengal lies under forests ?
Answer:
About 14%.

Question 24.
Where do mangrove forests grow ?
Answer:
River deltas and coastal areas.

Question 25.
Which tree of Karnataka is world famous ?
Answer:
Sandalwood tree.

Question 26.
What is the shape of the coniferous trees?
Answer:
Tall, conical, with very less branching.

Question 27.
When was Sundarban declared as the ‘World Heritage forest’?
Answer:
1989.

Question 28.
What are the most important means of forest conservation ?
Answer:
Afforestation and increasing consciousness of people.

Question 29.
Which Union Territory of India has the largest forest cover ?
Answer:
Andaman and Nicobar islands.

Question 30.
What kind of trees are most found in India ?
Answer:
Dry deciduous trees.

Question 31.
How are forest fires caused ?
Answer:
Due to friction between the tree branches in the hot season in the torrid zone.

Question 32.
What special adaptations are seen in mangrove trees?
Answer:
Supporting roots and breathing roots.

Question 33.
What kind of a tree is rosewood?
Answer:
Evergreen tree.

Question 34.
What kind of trees grow in deserts?
Ans.
Xerophytas.

Question 35.
What are forests known as for their capability to control air pollution?
Answer:
Natural sponge.

Detailed explanations in West Bengal Board Class 10 Geography Book Solutions Chapter 5.5 Soils in India offer valuable context and analysis.

WBBSE Class 10 Geography Chapter 5.5 Question Answer – Soils in India

Answer in short : 2 Marks

Question 1.
What is Bhangar?
Answer:
Bhangar is the comparatively old alluvium found on the upper sides of river valleys. It is coarse and pebbly and a little less fertile. It contains ‘Kankar’ nodules in the sub-soil.

Question 2.
What is Khadar?
Answer:
Khadar is the relatively new, compact, fine and moist silt found in the flood plains and deltas. It is more sandy and free from ‘Kankar’ nodules and is very fertile.

Question 3.
What is the importance of Black soil ?
Answer:
Black soil is most suitable for cotton cultivation. It is also popularly known as black cotton soil. It is also good for sugarcane, wheat and groundnut. It is highly rich in minerals.

Question 4.
What are the features of Red Soils?
Answer:
Red soils develop on crystalline igneous rocks in areas of poor rainfall. It is more sandy and less clayey. It is reddish in colour due to its high iron content.

Question 5.
What are the characteristics of Saline soils ?
Answer:
Saline soils are black, heavy and highly acidic. They are more sandy and less clayey. They are saline due to oceanic influence. They contain 10-40% organic matter.

Question 6.
What are the characteristics of Mountain Soils ?
Answer:
Mountain soils vary according to altitudes. They are rich in iron but deficient in lime. They are rich in humus and acidic in nature.

Question 7.
What do you mean by Soil erosion?
Answer:
Soil erosion refers to the breaking of soil particles by wind, rain, waves, snow, etc. and their removal from the surface.

Question 8.
Mention the direct consequences of soil erosion.
Answer:
The direct consequences of soil erosion are removal of fertile soil, degradation of agricultural land and inferior quality of vegetation.

Question 9.
What are the indirect consequences of soil erosion?
Answer:
The indirect consequences of soil erosion are – floods, siltation, fall of ground water landslide, economic set backs etc.

Question 10.
What is Strip Cropping ?

Answer:
Strip cropping refers to cultivation of crops in strips across the slope of the moutains, in order to break the slope to reduce soil erosion.

Question 11.
Mention the areas where alluvial soil is found.
Answer:
Alluvial soil is found in the river basins of Ganga, Indus and Brahmaputra in northern India. In southern India, it is found in the plains and deltas formed by rivers Mahanadi, Godavari, Krishna and Cauvery.

Question 12.
What are the characteristics of alluvial soil ?
Answer:
The main characteristics of alluvial soil are :

1. The soil is fine grained and is formed of sediments brought down by rivers.
2. The soil is rich in nutrients like calcium, phosphoric acid, lime and other substances.
3. It is rich in humus and potash.
4. It is very fertile and suitable for cultivation.

Question 13.
What are the types of alluvial soil ?
Answer:
Alluvial soil can be of two types – Bhangar and Khadar.

Question 14.
Why alluvial soil considered to be best for agriculture?
Answer:
Alluvial soil is rich in minerals and humus that is essential for crop growth. The soil is renewed every year by flooding of rivers. Hence, minerals get energy in the soil regularly. Thus it is most suitable for agriculture. Crops like rice, jute, vegetables and sugarcane grow very well in this soil.

Question 15.
Where is black soil found in India ?
Answer:
In India, black soil is found in the Deccan plateau, comprising Maharashtra plateau, Malwa plateau, Telengana-Rayaseema region of Andhra Pradesh, Northern parts of Karnataka, Gujarat and some parts of Tamil Nadu.

Question 16.
What are the characteristics of Black soil ?
Answer:

1. Black soil is black in colour.
2. It is also known as ‘Regur’ soil, derived from the latin work ‘Ragurgitare’.
3. The texture of the soil is clayey and water holding capacity of the soil is high.
4. The soil is sticky and hard.
5. It is rich in iron, calcium carbonate, potash and lime.

Question 17.
Why is Black soil rich in mineral content ?
Answer:
Black soil originates from basaltic rocks of lava plateaus. Hence, they are rich in minerals like iron, calcium carbonate, potash and lime. But it is poor in phosphates and organic matter.

Question 18.
Name the states of India where red soil is found.
Answer:
In India, Red soil is found in Kerala, Tamil Nadu, Karnataka, Andhra Pradesh, Odisha and Jharkhand.

Question 19.
Which crops can be grown in Red soil ?
Answer:
Red soil is suitable for growing crops like rice, wheat, sugarcane, cotton, pulses etc.

Question 20.
Where is lateritic soil found in India?
Answer:
Lateritic soil is found in the hilly areas of the Western Ghats, Chotanagpur plateau and the hills of Meghalaya.

Question 21.
What crops grow in Laterite soil ?
Answer:
Laterite soil is not very suitable for agriculture. Crops like cashew, tapioca, cotton, wheat etc. grow in this soil.

Question 22.
Where is Desert soil found in India ?
Answer:
Desert soil is found in Western Rajasthan, Northem Gujarat and Southern Punjab.

Question 23.
Which crops grow well in saline soils ?
Answer:
Coconut, beetle nut etc. grow well in saline soils.

Question 24.
What crops grow well in mountain soils?
Answer:
Mountain soils are found in the Himalayan region. They are suitable for growing tea, fruits, rice, etc.

Question 25.
How does surface run-off affect soil ?
Answer:
Surface run-off is an important reason for soil erosion. Rate of erosion depends on amount of rainfall, duration, size of water droplets and condition of the land surface (open or covered with vegetation).

Question 26.
In which region does wind cause maximum soil erosion ?
Answer:
Wind causes much soil erosion in open, tree-less and arid regions. It is predominant in desert regions.

Question 27.
How is overgrazing responsible for soil erosion ?
Answer:
Overgrazing on pastures cause exposure of soil to agents of erosion due to removal of vegetative cover. Thus it speeds up soil erosion.

Question 28.
Name two natural phenomena that may cause soil erosion.
Answer:
Soil erosion can be caused due to landslides and forest-fires.

Question 29.
How does nature of rainfall affect soil ?
Answer:
Nature of rainfall can be beneficial or harmful to soil. Slow and light rainfall helps to recharge underground water by percolation of water. But torrential showers and big size of rain drops cause the soil to loosen and wash away, hence causing erosion.

Question 30.
Why is removal of top soil harmful ?
Answer:
The top soil is the most fertile part of the soil. It contains most of the essential nutrients and humus, which help in plant growth. Removal of top soil by erosion removes the fertility of the soil and reduces its capacity to support agriculture.

Question 31.
What is contour farming?
Answer:
In mountainous regions, a number of low or small dams are constructed across the slopes at equal heights. This prevents the rapid flow of water down the slopes, reducing soil erosion. This method of preventing soil erosion is called contour farming.

Question 32.
What is Gully ploughing ?
Answer:
In regions affected by gully erosion, dams can be built across gullies to prevent water flow. Plants can be planted along the dams to stop erosion.

Answer in brief : 3 Marks

Question 1.
Mention the major areas of India that have been affected by soil erosion.
Answer:
Soil erosion is predominant in tropical monsoon climatic regions, desert regions, mountainous regions etc.

The areas of India affected by soil erosion are :

1. Nilgiri hills due to intence potato cultivation without proper terracing.
2. Gujarat, Maharashtra, Karnataka, Madhya Pradesh etc. due to gully erosion.
3. Punjab, Maharashtra, Madhya Pradesh etc. due to uncertain rainfall.
4. Rajasthan and Gujarat due to moving sand dunes and coastal soil erosion.

Question 2.
Discuss the direct consequences of soil erosion.
Answer:
The direct consequences of soil erosion are –
(a) Removal of fertile soil : Removal of humus and minerals from the soil surface makes it infertile.
(b) Degradation of agricultural land : Removal of essential minerals and humus from soil reduces its productivity and degrades agricultural land.
(c) Effects on Vegetation : Degradation of soil leads to inferior quality of vegetation due to lack of nutrients.

Question 3.
What are the indirect consequences of soil erosion ?
Answer:
The indirect consequences of soil erosion are :
(a) Floods : The eroded materials get deposited in the river valleys and raise the height of the river beds. Hence, carrying capacity of the channels get reduced, causing floods.
(b) Siltation : Regular deposition of sand, silt, clay, etc, in rivers, lakes, etc. causes formation of sand bars.
(c) Fall of ground water : Soil cover helps to absorb rain water gradually and recharge ground water. If soil cover is removed, water falls on hard rocky surface and slips away before absorption.
(d) Land slide : Soil erosion due to deforestation of mountain slopes causes rocks and boulders to loosen, resulting in landslides.
(e) Econonic set back: Agriculture suffers a lot due to soil erosion. This results in a severe economic set back.

Question 4.
Differentiate between Bhangar and Khadar soils.
Answer:

Bhangar	Khadar
i. Made up of old alluvium.	i. Made up of new alluvium.
ii. Comparatively old, coarse and less fertile.	ii. Relatively new, fine and fertile.
iii. Found in the upper sides of the river valleys.	iii. Found in the flood plains and deltas of rivers.
iv. Silt is pebbly and contains Kankar nodules.	iv. Silt is fine and free from Kankar nodules.
v. Soil is dry, porous and sandy.	v. Soil is moist, fine and compact.

Question 5.
Compare between Red soil and Laterite soil.
Answer:

Red Soil	Laterite Soil
i. Formed by less eluviation in comparatively drier and hot regions.	i. Formed by high eluviation and removal of silica from top soil by heavy rainfall.
ii. Found in tropical and sub tropical areas of less rainfall.	ii. Found in hot wet tropical regions.
iii. Usually formed by chemical reactions in soils due to excessive temperature.	iii. Usually formed by mechanical actions of eluviation.
iv. Found in Chotanagpur region.	iv. Found in small parts of Deccan plateau.
v. Mainly formed from granite and gneiss rocks.	v. Mainly formed from basalt and traces of granite.

Question 6.
Compare between Desert soil and Saline soil.
Answer:

Desert soil	Saline soil
i. Found in arid and semi arid regions of Western Rajasthan, Northern Gujarat and Southern Punjab.	i. Found along the eastern and western coasts of India.
ii. It is coarse and Sandy in texture (90-95% sand particles).	ii. It contains sandy as well as clayey soil particles.
iii. It contains high percentage of soluble salts.	iii. It contains 10-40 % of organic matter.
iv. It is highly alkaline in nature.	iv. It is highly acidic in nature.
v. It is poor in organic matter and not fertile.	v. It is saline in nature due to oceanic influence and not fertile.
vi. Crops like millets are grown.	vi. Crops like coconut and beetle nut are grown.

Question 7.
Write a short note on the regions that face severe soil erosion in India.
Answer:
Soil erosion is most predominant in regions where the agents of mechanical weathering are highly active. Eg. : Tropical monsoon climatic regions, desert regions, mountainous regions etc.
The scenario of soil erosion in India is as follows :

1. Potato cultivation without proper terracing in the Nilgiris has led to high erosion.
2. Gully erosion has affected regions in Gujarat, Maharashtra, Karnataka, Madhya Pradesh etc.
3. Uncertain rainfall has speeded up erosion in Punjab, Maharashtra, Madhya Pradesh etc.
4. Coastal soil erosion and movement of sand dunes have affected Gujarat etc.

Answer in details : 5 Marks

Question 1.
Discuss the causes of soil erosion.
Answer:
The various causes of soil erosion are:

1. Surface runoff : Soil is highly eroded by surface runoff of rain water. Rate of erosion depends on amount of rainfall, duration, size of raindrops and condition of land surface (open or covered with vegetation).
2. Wind : Wind causes much soil erosion is open, tree-less and arid regions.
3. Topography : Level of soil erosion is higher on mountain slopes than on plain lands due to the effect of gravitational force.
4. Pressure of excessive population on land: Excessive population compels use of land for several social and economic activities, for which natural vegetation has to be cut off. This increases the level of soil erosion.
5. Over-grazing : Over-grazing on pastures causes exposure of soil to the agents of erosion due to removal of vegetative cover.
6. Unscientific mining : Unscientific mining may cause subsidence or collapse of land, leading to heavy rates of soil erosion.
7. Landslide : Landslides on mountain slopes expose soil to the agents of erosion.
8. Deforestation : Cutting down of trees loosen the top soil and increases the rate of erosion.
9. Nature of rainfall : Torrential showers and big drops of rain cause the top soil to loosen and wash away easily.
10. Methods of farming : Cultivation of the same crop every year reduces the quality of soil and tends to increase erosion.
11. Others : Phenomena like floods, droughts, volcanic activities, earthquakes, forest fires etc. also cause soil erosion.

Question 2.
Discuss the methods of Soil conservation.
Answer:
The different methods of soil conservation are :

1. Afforestation : More and more trees should be planted especially on open or barren lands.
2. Terracing : Terracing of mountain slopes reduces the gradient and prevents soil erosion by washing away.
3. Strip cropping : Cultivation of crops in strips across the slope of the mountains help in breaking the slope, hence reduces erosion.
4. Contour farming : In this method, a number of small dams are built at equal heights of mountain slopes. This prevents rapid flow of water along the slopes, thus reducing soil erosion.
5. Shelter belt : Planting tall trees across the direction of wind flow helps to reduce soil erosion.
6. Controllod grazing : Scope should be left for grasses to grow again in between grazing, so that the vegetative cover does not get removed totally.
7. Stopping shifting cultivation : Primitive methods like shifting cultivation (egJhum cultivation) on mountain slopes and forested lands must be stopped in order to prevent soil erosion.
8. Gully plouging : In regions affected by gully erosion, dams can be built across gullies to prevent waterflow. Trees can be planted along the dams to stop erosion.

Question 3.
Describe the different types of soils found in India.
Answer:
The different type of soils found in India are :
i. Alluvial soil : This is a very fertile soil found in the river valleys, flood plains and deltas of rivers Ganga, Indus, Brahmaputra, Mahanadi, Godavari, Krishna, Kaveri etc. The soil is rich is calcium, phosphoric acid, lime, potash, humus etc. This soil is the best for agriculture.

ii. Black soil : Commonly known as Regur, this is a black, clayey, sticky and hard soil that originates from basaltic rocks of lava plateaus, especially the Deccan plateau region. It is good for growing cotton, sugarcane, wheat, groundnut etc.

iii. Red soil : This is a reddish infertile soil that develops from crystalline igneous rocks in areas of poor rainfall. It is found in Kerala, Tamil Nadu, Karnataka, Andhra Pradesh, Odisha and Jharkhand.

iv. Laterite soil : This soil is found in areas of heavy rainfall in the Western Ghats, Chotanagpur and hills of Meghalaya. It is an infertile soil formed by leaching away of minerals from the top layers. Crops like cashew, tapioca, cotton, wheat etc. grow in very less amount in this soil.

v. Desert soil : This is a coarse, sandy, porous, infertile soil found in arid regions of Western Rajasthan, Northern Gujarat and Southern Punjab. It is poor in organic matter and rich in soluble salts.

vi. Saline soil : This is found along the eastern and western coastal regions of India. The soil is black, heavy, acidic and full of organic matter. It contains both sand and clay particles. It is saline due to oceanic actions.

vii. Mountain soil : This is an acidic soil rich in iron content but deficient of lime. This is found in the mountainous regions of the Himalaya. This is suitable for growing tea, fruits, rice etc.

Question 4.
How does the presence of different types of soil in different parts of India influence the economy of the county?
Answer:
India is a huge country and has different kinds of soil in different parts of the country. Each soil has its own characteristics, hence influences the economy differently.
i. Presence of alluvial soil in the river valleys, flood plains, delta regions etc. makes them highly fertile and promotes very high levels of agriculture. Thus, presence of this soil makes India basically an agricultural country.

ii. Apart from alluvial soil, the other soils present in the country are also used for growing crops. Different types of soil help in growing different kinds of crops. Hence, a variety of crops can easily be grown in India.

iii. The variety of soils produce a variety of crops, which help to need various demands of the economy. Some soils are used for growing food crops (eg. alluvial soil grows rice well). Some soils help to grow cash crops (eg. black cotton soil helps to grow cotton, sugarcane etc.) Some soils help to grow beverage crops (eg. mountain soils help to grow tea and coffee).

iv. Different types of soil have different structures and textures. Hence, the hardness of the land surface, the porosity, water holding capacity etc. of a region depend upon what kind of soil the region is made up of. This in turn influences other economic activities. Eg- building of roads, railway lines, high rise buildings etc. are dependent on the quality of the soil.

Question 5.
What are the necessities of soil conservation?
Answer:
The process of preventing soil erosion and degradation by natural as well as artificial methods is known as ‘soil conservation’. The necessities of soil conservation can be listed as follows :

1. The top soil must be protected from washing away so that essential nutrients are not lost due to erosion.
2. Removal of essential nutrients from soil reduces productivity of the land. Soil must be protected to prevent degradation of agricultural land.
3. Inferior soil will lead to inferior crops. Soils must be protected to ensure good crops with respect to quality and quantity.
4. Washing away of soils leads to blocking and raising of river beds. This leads to frequent flooding of the rivers. Hence soil erosion must be controlled to control flood.
5. Soil erosion leads to high levels of siltation and formation of sandbars. This may cause rivers to change directions and cause devastations. Hence soil erosion must be checked.
6. Soil helps to absorb rain water and recharge the underground water reserve. Erosion of soil will reduce seepage of water considerably.
7. Soil erosion due to deforestation on mountain slopes lead to landslides. Hence, protection of soil cover on mountain slopes is very essential.
8. Soil is a very important factor of economic development. It influences agriculture, industrial growth, construction of railways, roadways and buildings. Hence, loss of soil cover will lead to a set back in economic development.

Multiple Choice Questions (MCQ) 1 Mark

Question 1.
The new alluvium found near the Ganga river is called
(A) Tarai
(B) Bhabar
(C) Khadar
(D) Bhangar
Answer:
(C) Khadar

Question 2.
Which state has very little alluvial soil area ?
(A) Tamil Nadu
(B) Haryana
(C) Madhya Pradesh
(D) West Bengal
Answer:
(C) Madhya Pradesh

Question 3.
Khadar soils are found
(A) In piedmont plains
(B) In flood plains
(C) Over low plateau
(D) Over steep slopes
Answer:
(B) In flood plains

Question 4.
The old alluvium of the river valleys of North Indian plains is known as
(A) Bhangar
(B) Khadar
(C) Bhur
(D) Bhabar
Answer:
(A) Bhangar

Question 5.
Laterite soil are found in the
(A) Rajasthan desert
(B) Chotanagpur plateau
(C) Ganga plain
(D) Punjab plain
Answer:
(B) Chotanagpur plateau

Question 6.
The alluvial soil is
(A) Dry, porous and sandy
(B) Black
(C) Brown
(D) Consistent of chemicals
Answer:
(A) Dry, porous and sandy

Question 7.
The Alluvial soil can
(A) Dry up in no time
(B) Contain moisture for long
(C) Be found on high mountains
(D) Turn into a rock which is a hardened mass
Answer:
(A) Dry up in no time

Question 8.
The fertility of the soil depends upon :
(A) Free availability of water
(B) Presence of chemicals and other elements
(C) Rotation of crops
(D) A single crop a year
Answer:
(B) Presence of chemicals and other elements

Question 9.
Alluvial Soil is that soil which :
(A) Comprises silt brought by the rivers
(B) Is sandy
(C) Is found on the mountains
(D) Is found in the forests
Answer:
(A) Comprises silt brought by the rivers

Question 10.
Black Soil is formed mostly on account of :
(A) Its continuous existence in hotter regions
(B) Non-availablity of enough water of the rivers
(C) The lava of the volcanoes
(D) The speedy flow of the rivers down the mountains
Answer:
(C) The lava of the volcanoes

Question 11.
Black Soil is :
(A) Porous, dry and sandy
(B) Sticky and compact
(C) Rocky in outlook
(D) Marshy in character
Answer:
(B) Sticky and compact

Question 12.
In India we can find Black soil in Madhya Pradesh, Andhra Pradesh, Tamil Nadu and _______ state:
(A) Bihar
(B) Rajasthan
(C) Odisha
(D) Maharashtra
Answer:
(D) Maharashtra

Question 13.
Red Soil is mostly find where we find :
(A) Proximity of the sea
(B) Proximity of the rivers
(C) Crystalline rocks
(D) Stratified rocks
Answer:
(C) Crystalline rocks

Question 14.
We find ‘Red Soil’ in :
(A) J & K State
(B) Himachal Pradesh
(C) Assam
(D) Bengal and parts of Maharashtra
Answer:
(D) Bengal and parts of Maharashtra

Question 15.
Laterite Soil is formed :
(A) During the alternate periods of dry and wet weatheral spells
(B) Near the mountains and rivers
(C) Near the springs of water
(D) Near the rivers only
Answer:
(A) During the alternate periods of dry and wet weatheral spells

Question 16.
The largest and the most important of the soils in India is _________ soil.
(A) Laterite
(B) Black
(C) Red
(D) Alluvial
Answer:
(D) Alluvial

Question 17.
Red soils cover an area of _________ of the total cultivated area.
(A) 11 %
(B) 18%
(C) 15 %
(D) 20%
Answer:
(A) 11 %

Question 18.
These soils which are very porous are ________
(A) Brown soils
(B) Red soils
(C) Black soils
(D) Desert soils
Answer:
(D) Desert soils

Question 19.
The earth’s crust which consists of loose materials is generally called __________
(A) Rocks
(B) Oil
(C) Minerals
(D) Soils
Answer:
(D) Soils

Question 20.
With a lot of irrigation and manuring __________ soil can be used for cultivation.
(A) Charnozem
(B) Black
(C) Laterite
(D) Red
Answer:
(D) Red

Question 21.
Due to rapid evaporation desert soil becomes _________
(A) Loose
(B) Wet
(C) Saline
(D) Muddy
Answer:
(C) Saline

Question 22.
_________ prevent the spread of ravines.
(A) Plough
(B) Rain
(C) Clouds
(D) Check dams
Answer:
(D) Check dams

Question 23.
The soil has been classified into major groups by the ICAR ________
(A) Five
(B) Eight
(C) Ten
(D) Six
Answer:
(B) Eight

Question 24.
Alluvial soil lacks this content _________
(A) Porous
(B) Lime
(C) Nitrogenous
(D) Potash
Answer:
(C) Nitrogenous

Question 25.
The most typical soil of the Deccan region is this soil ___________
(A) Brown
(B) Laterite
(C) Black
(D) Red
Answer:
(B) Laterite

Question 26.
The presence of this oxide gives red colour to the soil ______
(A) Silicon
(B) Iron
(C) Calcium
(D) Magnesium
Answer:
(B) Iron

Question 27.
This soil supports pasture lands ______
(A) Chernozem
(B) Red
(C) Laterite
(D) Black
Answer:
(C) Laterite

Question 28.
The character of hill-soil varies according to _______
(A) Cloud
(B) Altitude
(C) Air pressure
(D) Wind direction
Answer:
(B) Altitude

Question 29.
Cotton grows well on ____________
(A) Brown soil
(B) Alluvial soil
(C) Black soil
(D) Red soil
Answer:
(C) Black soil

Question 30.
Near the Eastern Ghats and some elevated territories of Madhya Pradesh we find :
(A) Black soil
(B) Alluvial soil
(C) Laterite soil
(D) Red soil
Answer:
(C) Laterite soil

Question 31.
The driest soil is :
(A) Desert soil
(B) Black soil
(C) Red soil
(D) Saline soil
Answer:
(A) Desert soil

Question 32.
Soil Exhaustion means :
(A) The exhaustion of the fertility of the soil
(B) The removal of soil through the process of weathering
(C) The removal of soil through floods
(D) None of these
Answer:
(A) The exhaustion of the fertility of the soil

Question 33.
A mixture of sand, clay and silt is known as
(A) Loan
(B) Clayey soil
(C) Black soil
(D) Red soil
Answer:
(A) Loan

Question 34.
Alluvial soils generally have a low content of
(A) Nitrogen
(B) Phosphorus
(C) Potash
(D) All of these
Answer:
(D) All of these

Question 35.
________ is not found in black soil.
(A) Iron
(B) Magnesium
(C) Aluminium
(D) Phosphorus
Answer:
(D) Phosphorus

Question 36.
Black soils develop mostly under
(A) Arid conditions
(B) Semi-arid conditions
(C) Humid conditions
(D) None of these
Answer:
(B) Semi-arid conditions

Question 37.
soil is found in the Mizoram and Shillong plateau.
(A) Laterite soil
(B) Black soil
(C) Alluvial soil
(D) Red soil
Answer:
(D) Red soil

Question 38.
Red soil is poor in –
(A) Phosphorus
(B) Nitrogen
(C) Lime
(D) All of these
Answer:
(D) All of these

Question 39.
The sandy soil of Rajasthan is called –
(A) Khadar
(B) Bhangar
(C) Kollar
(D) Bhur
Answer:
(D) Bhur

Question 40.
Loam is regarded as the most suitable type of soil for crop cultivation because –
(A) It can hold enough water
(B) It drains well
(C) It contains adequate quantities of humus
(D) All of these
Answer:
(D) All of these

Fill in the blanks : 1 Mark

1. Podzol soil is found in _______ areas.
2. _______ soil areas are regarded as vegetative lands.
3. Granite and gneiss rocks break dam to form _______ soil.
4. _______ soil is very suitable for cultivation of saffron.
5. Excessive irrigation leads to increase in _______ of soil.
Answer :
1. Mountainous
2. Kallar
3. Red
4. Karewa
5. Salinity

State True or False : 1. Mark

1. Mountainous soil is naturally acidic and infertile in nature. [ ]
2. The newly deposited alluvial in a river valley is called regur. [ ]
3. Desert soils have more water holding capacities. [ ]
4. In winter season, landslides lead to soil erosion. [ ]
5. Laterite soil is commonly seen in desert regions. [ ]
6. Alluvial soil is good for cotton cultivation. [ ]
7. Millets grow well in desert soils. [ ]
8. Red soil is found in the Andaman and Nicobar Island. [ ]
9. Much aluviation occurs in laterite soil. [ ]
10. The soil research centre of India situated in Jodhpur. [ ]
Answer:
1. True
2. False
3. False
4. False
5. False
6. False
7. True
8. True
9. True
10. True

Match the following : 1 Mark

Region	Soil type
A. Malwa plateau	1. Alluvial
B. Dharwar plateau	2. Laterite
C. Punjab plains	3. Red
D. Western ghats	4. Regur

Answer:

Region	Soil type
A. Malwa plateau	4. Regur
B. Dharwar plateau	3. Red
C. Punjab plains	1. Alluvial
D. Western ghats	2. Laterite

Answer in few words : 1 Mark

Question 1.
Where is alluvial soil found in Northern India?
Answer:
In the river basins of Ganga, Indus and Brahmaputra.

Question 2.
Where is alluvial soil found in peninsular India?
Answer:
The plains of Gujarat and deltas of rivers Mahanadi, Godavari, Krishna and Cauvery.

Question 3.
What is new alluvial soil known as?
Answer:
Khadar.

Question 4.
What is old alluvial soil known as ?
Answer:
Bhangar.

Question 5.
What is the other name of Black soil ?
Answer:
Ragur soil.

Question 6.
Name the areas where regur soil is found.
Answer:
Regur is found in the Deccan plateau, comprising Maharashtra plateau, Malwa plateau, Telengana-Raylaseema region of Andhra Pradesh, northern Karnataka, parts of Tamil Nadu and Gujarat.

Question 7.
Where is Laterite soil found in India?
Answer:
Hilly areas of Western Ghats, Chotanagpur plateau and hills of Meghalaya.

Question 8.
Where is red soil found in India ?
Answer:
Kerala, Tamil Nadu, Karnataka, Andhra Pradesh, Odisha and Jharkhand.

Question 9.
Where is desert soil found in India ?
Answer:
Western Rajasthan, Northern Gujarat and Southern Punjab.

Question 10.
Where is saline soil found in India?
Answer:
East and West coast of India and around the islands.

Question 11.
Where is Mountain soil found in India?
Answer:
Himalayan region.

Question 12.
What is Afforestation?
Answer:
Planting of trees on open and barren lands to prevent soil erosion, etc.

Question 13.
What is the method of reducing the gradient of slope to reduce soil erosion called?
Answer:
Terracing.

Question 14.
What do you mean by ‘Shelter Belt’ ?
Answer:
Planting of tall trees against the wind direction to prevent soil erosion.

Question 15.
What is siltation?
Answer:
Regular deposition of sand, silt, clay, etc. in rivers, lakes and other water bodies.

Detailed explanations in West Bengal Board Class 10 Geography Book Solutions Chapter 5.4 Climate of India offer valuable context and analysis.

WBBSE Class 10 Geography Chapter 5.4 Question Answer – Climate of India

Answer in brief : 2 Marks

Question 1.
How does the Tropic of Cancer influence the climate of India?
Answer:
The Tropic of Cancer passes almost through the middle of India. It divides India into two broad temperature zones. The southern half lies in the Torrid zone and the northern half lies in the Temperate zone.

Question 2.
How India is saved from severe cold polar winds ?
Answer:
The lofty Himalayas lying on the northern boundary of India form a natural barrier and prevent the severely cold polar winds blowing from the north to enter the land. Thus India is saved from severely chilled winters.

Question 3.
What is the difference in climate between Delhi and Chennai ?
Answer:
Delhi lies far away from the influence of the sea. Hence, it experiences extreme or continental climate. Chennai lies on the sea coast. Hence, it experiences moderate or maritime climate.

Question 4.
With what winds can the monsoon winds be compared ?
Answer:
Sea breeze and land breeze on a large scale.

Question 5.
Why are the South-West monsoon winds moisture laden ?
Answer:
The South-West monsoon winds generate over the Indian ocean. They cross the Bay of Bengal and the Arabian Sea on the East and West respectively before entering the land. Hence, the winds are moisture laden.

Question 6.
Why are the north-east monsoon wind dry ?
Answer:
The north-east monsoon wind or the retreating monsoon winds blow over the land towards the sea. They have very little source of collecting moisture. Hence they are comparatively dry. But a small portion of the winds passes over the Bay of Bengal and re-enter the mainland near Tamil Nadu. This portion of the winds is moisture laden and sheds the waters in Tamil Nadu coast before finally leaving the country.

Question 7.
What is ‘Kalbaishakhi’ or Norwesters ?
Answer:
‘Kalbaisakhi’ or Norwesters are violent local cyclonic storms common in eastern coastal regions of India. They are accompanied with thunder and lightning, heavy showers and sometimes hail. They occur during summer season (AprilMay) due to sudden formation. of low pressure cells on the land near coastal areas.

Question 8.
What is the difference in rainfall between the Eastern and Western ghats?
Answer:
The Arabian sea branch of the south-west monsoon causes heavy rainfall on the coastal areas of the Western Ghats (over 300 cm) because they lie in the windward side. The Deccan plateau and the Eastern Ghats receive lesser rainfall as they lie in the leeward side or in the rain-shadow area.

Question 9.
Which region of India receives the highest rainfall in India ?
Answer:
Mawsynram near Cherrapunji in Meghalaya on the southern slope of GaroKhasi-Jayantia hills in Meghalaya plateau receives the highest amount of rainfall in India as well as the world. (highest recorded 1142 cm).

Question 10.
How the Indian economy is controlled by the monsoon ?
Answer:
India is an agro-based economy. About 14% of Gross Domestic Product comes from agriculture. Agriculture is highly dependent on the monsoon winds/rainfall. Hence, monsoon plays an important role in controlling the Indian economy.

Question 11.
How does the latitudinal extent of India influence the climate?
Answer:
India stretches from 8.4′ N to 37°6′ N latitudes. The southem part of India till the 30° N latitude receives almost vertical rays of the sun and experiences tropical climate. The region lying north of the 30° N latitude receives slanting rays of the sun and experiences temperate climate in general.

Question 12.
How does presence of mountains influence the climate of India ?
Answer:
The presence of Western Ghats, Himalayas and Garo, Khasi hills help in the occurrence of rainfall from the South-West monsoons. Also, the Himalayas prevent the chilled Siberian wind of the polar regions from entering the country and giving it a chilling climate.

Question 13.
How does altitude control the climate of India ?
Answer:
Temperature reduces by 6.4°C with rise of 1000 m in altitude by the normal lapse rate. Hence, the hilly regions of the Karakoram and Himalayan ranges, the Ladakh plateau and other adjacent highlands enjoy a cool summer in spite of being situated in the low latitudes. During winter, many regions receive snowfall. The Western Ghats and Eastern Ghats also remain cooler due to high altitude even though located towards the equator.

Question 14.
What is the influence of the Aravalli range in the climate of Rajasthan?
Answer:
The Aravalli range lies in the eastern margin of Rajasthan in the North-East to South-West direction. The South-West monsoon wind entering from the Arabian sea blows almost parallel to the Aravalli range. Thus, these mountains cannot stop the moisture laden monsoon wind, which escapes towards further NorthWest. Hence, very little rainfall occurs here (less than 25 cm yearly), giving rise to the Thar desert.

Question 15.
Why does Shillong receive very less rainfall in spite of lying very close to Cherrapunji which receives the highest rainfall ?
Answer:
Cherrapunji is located on the windward slope of the Khasi hills in Meghalaya. The South-Western monsoons hit against this slope and cause enough rainfall in Cherrapunji. But Shillong lies on the leeward side of the Khasi hills in the rain shadow area. Hence, it receives very less rainfall even though physical distance between the two places is not quite much.

Question 16.
What do you mean by ‘Burst of monsoon’ ?
Answer:
By the first week of June, the moisture laden South-West monsoon winds hit against the Western Ghats near the Malabar coast and in Kerala. This brings forth the first rains for the country from the monsoon winds. This is known as the ‘Burst of monsoons’. By the middle of July, the monsoon winds spread over most of the country and provide enough rainfall.

Question 17.
What is ‘Andhi’?
Answer:
‘Andhi’ is a hot sandy storm that occurs in the Thar desert of Rajasthan and adjacent areas during the summer. Wind speed may be 50-60 km per hour. It is a dry wind and does not cause any rainfall.

Question 18.
What do you mean by ‘Western disturbances’?
Answer:
During the winter, winds coming from the Mediterranean region due to the influence of the Westerlies, cause the occurrence of weak cyclones. Due to this, the states of North-West India, i.e. Punjab, Haryana, Rajasthan etc. receive light rainfall and the hilly regions of the north receive much snowfall. This wind is called the ‘Western disturbances’.

Question 19.
Which states receive snowfall in winter in India ?
Answer:
In India, the states that receive snowfall in winter are – Jammu and Kashmir, Himachal Pradesh, Uttarakhand, Sikkim and northern part of West Bengal (Darjeeling).

Question 20.
Which winds cause rainfall in Tamil Nadu ?
Answer:
Tamil Nadu receives rainfall by the influence of two winds – the South-West monsoon or the ongoing monsoons and the north-east monsoon or the retreating monsoon.

Question 21.
Which regions of India receive rainfall in the winters?
Answer:
The areas that receive rainfall in the winter are :
(i) Under the influence of retreating monsoon : Coromondal coast of Tamil Nadu.
(ii) Under the influence of Western disturbances : Jammu and Kashmir, Rajasthan, Punjab, Haryana, Uttar Pradesh, Uttarakhand, Bihar and some parts of West Bengal.

Question 22.
Which regions of India receive very high rainfall ?
Answer:
The regions in India that receive very high rainfall (over 200 cm) are – the western slope of the Western Ghats, the eastern Himalayas, the North-Eastern hilly region, Mizoram, North Bengal, Andaman and Nicobar islands etc.

Question 23.
Which regions of India receive less to very less rainfall ?
Answer:
The regions of India receiving less to very less rainfall (lower than 20 cm to 60 cm) are – the eastern slope of the Western Ghats, Punjab, Haryana, Rajasthan, Ladakh Valley of Kashmir etc.

Question 24.
Why winter is dry in India ?
Answer:
During winter, the north-east monsoon wind blow from the land towards the sea.
It cannot collect enough moisture in its way due to lack of water bodies. The moisture holding capacity of this wind is also low. Hence, it fails to provide rainfall, and makes the winter dry.

Question 25.
What do you mean by ‘drought’ ?
Answer:
Drought is the condition of very less or no rainfall over an area over a long period of time. Thus causes the soil to dry up tremendously and become unfit for plants to survive. About 34% area of India is under drought.

Question 26.
Name the drought prone areas of India.
Answer:
About 34% of India’s area is under the influence of drought, of which 16% area is under severe drought. The drought prone areas of India are –

1. Desert and semi-desert regions of Rajasthan.
2. The middle part of Western Ghats and Eastern Ghats.
3. Kutch and Saurashtra region of Gujarat.
4. Purulia of West Bengal.
5. Kalahandi of Odisha.

Question 27.
What is flood?
Answer:
If a region receives 125% more rainfall than its usual rate, the water logged condition thus created is called a flood. Also, rainfall in one region may increase the water level of the rivers so much that they cause floods in some other areas.

Question 28.
Which are the flood prone areas of India ?
Answer:
About 12% of India’s area remains under floods per year. The main flood-prone areas are :

1. Brahmaputra valley of Assam.
2. The river valleys of Yamuna, Chambal, Ghaghra of the Gangetic plains.
3. Damodar valley.
4. Terai and Duars region of the foothills of the Himalaya.

Answer in brief : 3 Marks

Question 1.
What is a jet stream ?
Answer:
Jet stream is a thin stream of speedy winds (350-450 km/hr) that blow from west to east from the winter till March-April between the Troposphere and the Stratosphere. These winds influence the onset and retreat of the monsoons in India, by seasonal shifting and creation of low pressure and high pressure cells respectively.

Question 2.
Describe the cold season in India.
Answer:
The cold season prevails in India from December to February. January and February are the coldest months. The winds blow from the land. Hence, the atmosphere remains dry. Temperature remains around 10°-15°C in the northern part and around 25°C in the southern part. Sometimes, shallow cyclonic disturbances may be caused due to western disturbances. This may cause little rainfall which is beneficial for wheat cultivation in north-west India.

Question 3.
Describe the hot season in India ?
Answer:
The hot season prevails in India from March to May. In May, the average temperature reaches about 44°C in Jaisalmer, 41°C in Delhi, 35°C in Kolkata. A low pressure zone develops over the Indian desert to the Chotanagpur plateau. Around this low pressure cell, several local winds may set in. Eg- Loo, Andhi, Kalbaisakhi etc. The low pressure cell gradually becomes so intense, that it pulls or attracts the monsoon winds towards the mainland.

Question 4.
Describe the season of the retreating monsoon in India.
Answer:
The retreating of monsoon occurs from October to November. This actually begins to set in by the end of September when the low pressure cell over north western India becomes weak because the direct rays of the sun shift towards the

equator. The direction of the surface winds starts reversing and the monsoon is said to start ‘retreating’. These winds are also called North-east monsoon winds.

Question 5.
Why does Tamil Nadu receive rainfall twice a year?
Answer:
During summer, when an intense low pressure cell is developed over north-west India, the south-west monsoon wind is attracted towards the land. These winds generate over the Indian ocean and hence are moisture laden. As they enter the mainland, they cause rainfall to the Coromondal coast of Tamil Nadu.

During winter, when the low pressure cell of the land gets weakened, the wind blows in the reverse direction. These are dry winds blowing outward from the land, hence cause almost no rainfall. But a small branch of the retreating monsoons blow over the Bay of Bengal and re-enter the land. This portion of the wind is moisture laden and hence causes rainfall in Tamil Nadu before finally leaving the country. Thus Tamil Nadu receives rainfall twice a year.

Question 6.
Discuss the effect of mountains on the climate of India.
Answer:
The mountains that influence the climate of India are:
i. Himalayan range : The Himalaya prevents the chilled Siberian wind from entering the country from the north. It also stops the south-west monsoon wind from escaping outside the country. It helps the monsoon wind to cause orographic rainfall.
ii. Western Ghats : The western slopes of the Western Ghats receive much rainfall from the Arabian Sea branch of the monsoon wind. The eastern slope is a rain shadow area.
iii. Eastern Ghats : The retreating monsoon hits against the mountains and cause rainfall in the Coromondal coast in winter.
iv. Aravalli range : They lie parallel to the direction of the south-west monsoon, and fail to stop the moisture laden wind. The eastern slopes receive little rainfall but the western slope is almost dry.

Question 7.
How does the presence of oceans on three sides of India influence the climate?
Answer:

1. The climate of South India is more or less moderate due to influence of the sea breeze and land breeze.
2. The south-west monsoon wind collects enough moisture while blowing over the oceans and causes rainfall in India.
3. Cyclones generated in coastal areas cause storms and rainfall.

Question 8.
Why is India called a tropical monsoon country ?
Answer:
The climate of India is highly controlled by the south-west and north-east monsoons. About 90% rainfall occurs due to the south-west monsoon. The north-east monsoon keeps the season dry. The economy of India is much dependent on the onset of the monsoon winds. Thus, India is called a tropical monsoon country.

Question 9.
Why does the western part of India receive lesser rainfall than the eastern part?
Answer:
The Bay of Bengal branch of the south-west monsoon enters India from the eastern side, causes much rainfall in the Terai-Duars region and the north-eastern states and gradually move westwards. As they move, they shed water and by the time they reach the western side they have no moisture left. Again, the Arabian Sea branch of the monsoon wind that enters India from the west, passes over the western region as the Aravalli fails to stop the moisture laden winds. Thus, the western part of India receives lesser rainfall than the eastern part.

Answer in details : 5 Marks

Question 1.
Discuss the factors affecting climate of India.
Answer:
The factors that affect the climate of India are as follows:
i. Latitude : India lies between 8°4′ N and 39° 6′ N latitudes. The tropic of Cancer runs through the middle of the country dividing the land into two distinct temperature zones. The southern part belongs to the Torrid zone and the northern part belongs to the Temperate zone.

ii. Relief : Temperature is inversely proportional to altitude. Hence, high relief regions have cooler climate compared to lower regions. Eg- some regions of Deccan plateau enjoy cool summers due to altitude, inspite of being nearer to the equator than the northern plains. The coastal regions enjoy an equable climate throughout the year.

iii. The Hinalavas. The lofty Himalayas act as a barrier to the severely cold polar winds that come from the north, thus saving the country from chilling winters. It also prevents the monsoon winds from escaping northwards, thus ensuring monsoon rainfall in India.

iv. Distance from the rightarrow a : The regions near the long coastline of India enjoy maritime or moderate climate throughout the year due to the influence of the sea. Regions lying far away from the sea experience extreme or continental climate with harsh summers and winters.

v. Winds : India lies under the prevailing north-eastern trade winds. Due to inequal heating of land and sea in different seasons, section of the wind blow seasonally from opposite directions. These are called the monsoon winds. They have a remarkable impact on Indian climate and economy.

vi. Western disturbance: In winter, some cyclones of the Mediterranean region, called western disturbances, enter India causing a little rainfall in the north.

vii. stream : This is a thin stream of speedy winds (350-450 km/hr) blowing from west to east between the Troposphere and Stratosphere. These winds influence the onset and retreat of monsoons in India.

viii. F-Nino and La-Nina : El- Nino is associated with high pressure in western Pacific Ocean and low pressure in the eastern part. Warm ocean currents develop in eastern and central Pacific Ocean which influence the temperature and rainfall of the associated regions. La-Nina is just the reverse phenomena, resulting in sustained cooling of the same regions. They both have an impact on onset of monsoons in India and the moisture content of the winds.

Question 2.
Describe the monsoon in India.
Answer:
The monsoon prevails in India from June to September. In June, the sun shines directly on the Tropic of Cancer. The landmass gets highly heated and develops a low pressure cell in the north-western region. This low pressure cell attracts winds from oceanic high pressure regions and even the South-East Trade winds from south of the Equator. These winds are warm and carry enough moisture. They advance towards the landmass with furious speed and violent thunder and lightning. This is called the ‘Burst of Monsoon’.
On reaching the Indian sub-continent, the monsoon winds are divided into two

branches – The Bay of Bengal branch and the Arabian sea branch. The Arabian sea branch hits the western slopes of the Western ghats and causes immense rainfall. The Deccan plateau and the Eastern ghats lie in the rainshadow area and receive lesser rainfall. The Bay of Bengal branch strikes against the Himalayas and causes heavy rainfall in the north-eastern and eastern states. Mawsynram near Cherrapunji in Meghalaya receive the maximum rainfall in the world. Amount of rainfall recedes or reduces from east to west.

Question 3.
Discuss the impacts of monsoon winds on India.
Answer:
The monsoon winds have a great impact on the climate, vegetation, agriculture, soil, economy and daily life of India. They can be discussed as follows –

1. Most rainfall in India occurs in summer due to the south-west monsoon winds.
2. In winter, the retreating monsoon winds blow from land to sea, causing rainfall only to the Coromondal coast in the south-east.
3. The crop calendar of India depends on the monsoons.
4. Immense rainfall in some regions (Eg- foothills of Himalayas, western slope of Western ghats) bring about lush green vegetation, whereas, lack to rainfall makes the western part a desert.
5. Irregular rainfall may cause floods, droughts and result in crop failure.
6. The quality of soil, its structure, texture, water holding capacity etc. are also influenced by the presence of water in it.
7. Monsoon influences almost all economic activities in India. Eg-mining, fishing, industries, tourism etc.
8. The Gross Domestic Product of India, of which 14% comes from agriculture, is highly influenced by the monsoons.

Question 4.
Discuss the climatic characteristics of India.
Answer:

India is basically a tropical monsoon climatic country. The Meteorological Department of India identifies four seasons that prevail in the country.

i. The cold season or winter (December to February) : January and February are the coolest months in India. Temperature varies between 10°C-15°C in the northern parts and about 25°C in southern part of India. The winds generally dry as they blow from land towards the sea. In the north-western part, a series of shallow cyclones caused by western disturbances cause little rainfall. Such winter rainfall is beneficial for wheat cultivation in the north-western regions.

ii. The hot season or summer (March to May) : This period is marked by the shifting of heat zone from south to north. May is the hottest month, when average day time temperature

reaches 44°C in Jaisalmer, 41°C in Delhi, 35°C in Kolkata etc. A low pressure zone extends from the Indian desert upto the Chotanagpur plateau. Local hot dusty wind like Loo and Andhi are common in the north western regions. Gusty cyclonic winds called Kalbaishakhi is experienced in eastern coastal areas, which brings in torrential rainfalls.

iii. The South-West monsoon season (June to September) : The low pressure created on the landmass during summer helps to drag the

monsoon wind from the adjoining oceans. This wind is warm and moist and approaches towards the land with furious thunder and lightning. On reaching the land, they are divided into the Bay of Bengal and Arabian Sea branches. Most of the rainfall in India occurs due to the southwest monsoons. Mawsynram near Cherrapunji in Meghalaya is the wettest place of the world (1142 cm rainfall).

iv. The north-west monsoon or Retreating monsoon season (October to November) : This season begins from the end of September when the monsoonal low pressure becomes weak as the direct sunrays shift from the tropical region back southwards. The wind reverses and starts flowing out from land to sea. As the wind leaves the mainland, it causes the formation of small cyclones locally known as ‘Aswiner Jhar’ or the storms of autumn. It brings in some amount of rainfall.

Multiple Choice Questions (MCQ) : 1 Mark

Question 1.
Which of the following does not have influence over the climate in India?
(A) Nearness to equator
(B) Presence of Indian Ocean
(C) Monsoons
(D) Ocean currents
Answer:
(D) Ocean currents

Question 2.
The place in India receiving the lowest rainfall is :
(A) Leh
(B) Jaisalmer
(C) Bikaner
(D) Jodhpur
Answer:
(A) Leh

Question 3.
The western disturbances which cause winter rain in India originate in
(A) Pakistan
(B) Bay of Bengal
(C) West Asia
(D) Himalayas
Answer:
(C) West Asia

Question 4.
How do the ‘western disturbances’ affect the crops in north India?
(A) They cause heavy damage to the standing crops
(B) They bring in locusts which destroy the crops
(C) They are beneficial to the crops by causing winter rain
(D) They help in keeping the plants warm to some extent in winter
Answer:
(C) They are beneficial to the crops by causing winter rain

Question 5.
How do the Central Asian highlands affect the Indian climate?
(A) The low pressure in these areas intensifies the cold during the winter
(B) The atmospheric pressure in this region has an effect on the Indian atmosphere in summer
(C) Dry continental air is blowing towards India throughout
(D) The atmospheric pressure in this region has an impact on the onset of monsoon in India
Answer:
(D) The atmospheric pressure in this region has an impact on the onset of monsoon in India

Question 6.
Which of the following regions has the minimum seasonal variations in temperature?
(A) The Shillong Plateau
(B) Tamil Nadu
(C) The Kerala coast
(D) The entire peninsula
Answer:
(C) The Kerala coast

Question 7.
The wettest place found in the north-east of India is …
(A) Mawsynram
(B) Jacobabad
(C) Cherrapunji
(D) Kohima
Answer:
(A) Mawsynram

Question 8.
The place that gets rainfall from the western disturbances is …
(A) Agra
(B) Ahmedabad
(C) Mumbai
(D) Srinagar
Answer:
(D) Srinagar

Question 9.
The place which has the lowest mean temperature in January is …
(A) Kolkata
(B) Patna
(C) Lucknow
(D) Srinagar
Answer:
(D) Srinagar

Question 10.
The hottest month in Mumbai is
(A) July
(B) April
(C) May
(D) June
Answer:
(C) May

Question 11.
Tamil Nadu gets most of its rainfall in the months of …
(A) May-June
(B) March-April
(C) July-August
(D) October-November
Answer:
(D) October-November

Question 12.
During ……. difference in air pressure arises between large land masses of Asia and Indian Ocean in the South.
(A) Rainy
(B) Winter
(C) Summer
(D) Autumn
Answer:
(C) Summer

Question 13.
The monsoon winds have a effect on Indian climate.
(A) Disturbing
(B) Unifying
(C) Mystifying
(D) None
Answer:
(B) Unifying

Question 14.
Warm and moist winds blow from the oceans during …. and dry winds blow during winter.
(A) Summer
(B) Winter
(C) Hot
(D) Autumn
Answer:
(A) Summer

Question 15.
Western disturbances bring rainfall that promote cultivation of
(A) Wheat
(B) Ragi
(C) Rice
(D) Jute
Answer:
(A) Wheat

Question 16.
During the hot dry season, the low pressure trough extends from ____________ to the Chotanagpur plateau in the east.
(A) Deccan
(B) Malwa
(C) Rajasthan
(D) Ladakh
Answer:
(C) Rajasthan

Question 17.
The peninsular shape and the of the country modify the direction of wind approaching into India.
(A) Crops
(B) Lakes
(C) Relief
(D) Rivers
Answer:
(C) Relief

Question 18.
Bay of Bengal branch blows roughly parallel to the coast and Eastern Ghats.
(A) Konkan
(B) West
(C) Malabar
(D) Eastern
Answer:
(D) Eastern

Question 19.
Owing to rainfall and cloudiness, here is a fall in during the advancing Monsoon Season.
(A) Weather
(B) Pressure
(C) Temperature
(D) Seismisity
Answer:
(C) Temperature

Question 20.
Cool weather sets in by ________ in India.
(A) December
(B) October
(C) November
(D) September
Answer:
(A) December

Question 21.
In June the slopes of the Western Ghats receive heavy rainfall.
(A) Northern
(B) Eastern
(C) Western
(D) South-eastern
Answer:
(C) Western

Question 22.
The state of Assam falls in the region.
(A) Low rainfall
(B) Heavy rainfall
(C) Moderate rainfall
(D) Very heavy rainfall
Answer:
(B) Heavy rainfall

Question 23.
Monsoons are winds.
(A) Local
(B) Seasonal
(C) Permanent
(D) Temporary
Answer:
(B) Seasonal

Question 24.
Tropical cyclones in the Bay of Bengal are most frequent during
(A) March-April
(B) October-November
(C) May-June
(D) January-February
Answer:
(B) October-November

Question 25.
India lies to the north and south of the ….
(A) Arctic circle
(B) Tropic of Cancer
(C) Equator
(D) Tropic of Capricorn
Answer:
(B) Tropic of Cancer

Question 26.
The maximum rainfall area of India, i.e., Meghalaya has average annual rainfall of –
(A) 1050 cm
(B) 795 cm
(C) 1150 cm
(D) 1000 cm
Answer:
(A) 1050 cm

Question 27.
Driest areas of India which lie in Rajasthan have an average annual rainfall of –
(A) 100 cm
(B) 20 cm
(C) 10 cm
(D) Less than 1 cm
Answer:
(D) Less than 1 cm

Question 28.
In which region of India does monsoon type with cold humid winter and short summer prevail ?
(A) Kashmir
(B) South India coast of the Western Ghats
(C) North-East India
(D) The Central Indian Plateau
Answer:
(C) North-East India

Question 29.
Which of the following statements about the Indian monsoon is incorrect?
(A) South-West monsoon arc on-shore winds
(B) North-East monsoon arc off-shore winds
(C) The monsoon retreat gradually
(D) The onset of the monsoon is from West Bengal only
Answer:
(D) The onset of the monsoon is from West Bengal only

Question 30.
Which of the following does not get rains from the Arabian Sea current alone during the South-West monsoon?
(A) Gujarat
(B) Maharashtra
(C) Punjab
(D) Western Ghats
Answer:
(C) Punjab

Question 31.
The amount and intensity of monsoon rainfall is determined by the frequency of
(A) Western disturbances
(B) Dust-storms
(C) Cyclones
(D) Tropical depressions
Answer:
(D) Tropical depressions

Question 32.
One of the regions that receives rainfall from the North-easterly monsoon is
(A) Assam
(B) Kerala
(C) West Bengal
(D) Tamil Nadu
Answer:
(D) Tamil Nadu

Question 33.
The retreating South-West monsoon does not affect
(A) Tamil Nadu
(B) Odisha
(C) Andhra Pradesh
(D) Uttar Pradesh
Answer:
(D) Uttar Pradesh

Question 34.
Rajasthan receives very little rain because
(A) It is too hot
(B) There is no water available and thus the winds remain dry
(C) The monsoon fail to reach this area
(D) The winds do not come across any barrier to cause the necessary uplift to cool the winds
Answer:
(D) The winds do not come across any barrier to cause the necessary uplift to cool the winds

Question 35.
Which time of the day is generally the hottest period all over India?
(A) Noon
(B) 1 p.m.
(C) 2 p.m.
(D) One cannot say
Answer:
(C) 2 p.m.

Question 36.
The retreating monsoon withdraws itself from
(A) The west coast to the east coast
(B) North-East India to the west coast
(C) The north to the south
(D) North-West India to Bengal and then to Kerala
Answer:
(D) North-West India to Bengal and then to Kerala

Question 37.
How do dust storms in summer affect the temperature?
(A) Increase it
(B) Decrease it
(C) No effect
(D) Cannot say
Answer:
(B) Decrease it

Question 38.
At which place will you find maximum sunlight in December?
(A) Kanya Kumari
(B) Pune
(C) Calcutta
(D) Leh
Answer:
(A) Kanya Kumari

Question 39.
There is heavy rainfall on the western coast of India but very little in the Deccan because ..
(A) The Deccan plateau is situated in the rain shadow of the Western Ghats
(B) The region is bypassed by the South-West monsoons
(C) Lack of high mountains in the Deccan
(D) Of some unknown reasons
Answer:
(A) The Deccan plateau is situated in the rain shadow of the Western Ghats

Question 40.
In winter, Punjab gets rainfall from –
(A) North-eastern trade winds
(B) South-west monsoons
(C) Cydones coming from the Mediterranean sea
(D) Retreating monsoon
Answer:
(C) Cydones coming from the Mediterranean sea

Question 41.
Which of the following is incorrectly matched?
(A) Mango-shower-Kerala
(B) Kalbaisakhi – West Bengal
(C) Norwester – Maharashtra
(D) Loo-Haryana and Uttar Pradesh
Answer:
(C) Norwester – Maharashtra

Question 42.
Which of the following places receives maximum sunlight in December?
(A) Shillong
(B) Ranchi
(C) Kanyakumari
(D) Jodhpur
Answer:
(C) Kanyakumari

Question 43.
In which season is the frequency of tropica cyclones in the Bay of Bengal maximum?
(A) During monsoon
(B) After summer
(C) During winter
(D) During autumn
Answer:
(C) During winter

Question 44.
The retreating monsoon has maximum effect on-
(A) Orissa
(B) West Bengal
(C) Punjab
(D) Tamilnadu
Answer:
(D) Tamilnadu

Question 45.
The easterly depressions develop over the
(A) Rann of Kachch
(B) Bay of Bengal
(C) Indian Ocean
(D) Gulf of Cambay
Answer:
(B) Bay of Bengal

Question 46.
If a strong anticyclone develops on the Southern arc of the Arabian sea, it will
(A) Cause premature coming of monsoon
(B) Delay the monsoon
(C) Have no effect on monsoon
(D) Hamper the monsoon
Answer:
(B) Delay the monsoon

Question 47.
The coldest inhabited place ranking second in the world is
(A) Kullu (Himachal Pradesh)
(B) Manali (Himachal Pradesh)
(C) Itanagar (Arunachal Pradesh)
(D) Dras (Jammu & Kashmir)
Answer:
(D) Dras (Jammu & Kashmir)

Question 48.
Dust storms in the northem parts of Thar desert occur more frequently in
(A) April
(B) May
(C) March
(D) June
Answer:
(D) June

Question 49.
South-east trades cross the equator and reach the West coast of India as
(A) South-East trades
(B) South-West monsoons
(C) North-West tradess
(D) None of these
Answer:
(B) South-West monsoons

Question 50.
The easterly jet stream owes its origin to the
(A) Summer heating of the Arabian sea
(B) Summer heating of the Thar desert
(C) Summer heating of the Himalayan and Tibetan highlands
(D) Summer heating of the Arakan Yoma extension.
Answer:
(C) Summer heating of the Himalayan and Tibetan highlands

Fill in the blanks : 1 Mark

1. The western coast of India is warmer than the eastern coast by about ______ in winter season.
2. The normal date of the onset of the monsoon in Andaman and Nicobar islands is ______.
3. ______ is the hottest month in Srinagar and Shillong.
4. The norwesters (Kalbaisakhi of West Bengal) originate over the ______ plateau.
5. The thunderstorms and rains in the premonsoon time is known as ‘cherry blossoms’ in ______ state.
Answer:
1. 1.7°C
2. 20 may
3. July
4. Chotanagpur
5. Karnataka

Match the following : 1 Mark

List I (Rivers)	List II (Tributaries)
A. Asvina-Kartika	1. July-August
B. Jyestha-Asdha	2. November-December
C. Sravana-Bhadra	3. May-June
D. Margashirsha-Pausa	4. September-October

Answer:

List I (Rivers)	List II (Tributaries)
A. Asvina-Kartika	4. September-October
B. Jyestha-Asdha	3. May-June
C. Sravana-Bhadra	1. July-August
D. Margashirsha-Pausa	2. November-December

Answer in few words : 1 Mark

Question 1.
What is the general climate of India called?
Answer:
Tropical monsoon climate.

Question 2.
What is the relation between altitude and temperature?
Answer:
Temperature reduces by 6.4°C for every 1000 m rise in altitude.

Question 3.
What kind of climate is experienced by places near seas ?
Answer:
Moderate or Maritime climate.

Question 4.
What kind of climate is experienced by places far away from seas ?
Answer:
Extreme or continental climate.

Question 5.
Which planetary winds are associated with the monsoon winds?
Answer:
North-Eastern Trade winds.

Question 6.
Between which layers of the atmosphere does the Jet stream flow ?
Answer:
Between the Troposphere and Stratosphere.

Question 7.
Which months of the year comprise winter season in India ?
Answer:
December to February.

Question 8.
Which months comprise the summer season in India ?
Answer:
March to May.

Question 9.
Which months comprise the monsoon season in India ?
Answer:
June to September.

Question 10.
When does the monsoon winds retreat?
Answer:
October-November.

Question 11.
What is the major factor that controls the crop calendar in India ?
Answer:
The monsoon wind.

Question 12.
Which is the driest part of India?
Answer:
The western part of Rajasthan.

Question 13.
Which is the wettest part of India ?
Answer:
Mawsynram near Cherrapunji in Meghalaya in the east.

Question 14.
Which part of India receives rainfall twice a year?
Answer:
The South-Eastern coast or the Coromondal coast in coastal Tamil Nadu.

Question 15.
What are the cyclonic storms caused in summer in eastern coast called?
Answer:
‘Kalbaisakhi’ or Norwesters.

Detailed explanations in West Bengal Board Class 10 Geography Book Solutions Chapter 5.3 Water Resources of India offer valuable context and analysis.

WBBSE Class 10 Geography Chapter 5.3 Question Answer – Water Resources of India

Answer in short : 2 Marks

Question 1.
Name the countries through which the river Indus flows.
Answer:
Tibet, Jammu and Kashmir of India, and Pakistan.

Question 2.
Name the five tributaries of river Indus in India.
Answer:
Rivers Jhelum, Chenab, Ravi, Beas, Sutlej.

Question 3.
Name the left bank tributaries of Ganga.
Answer:
Rivers Gomoti, Ghagar, Kosi, Gandak.

Question 4.
Name the right bank tributaries of Ganga.
Answer:
Rivers Yamuna, Son, Damodar, Ajay.

Question 5.
Why is river Kosi called the Sorrow of Bihar ?
Answer:
The river Kosi causes much flood during the rainy season. Hence it is called the ‘Sorrow of Bihar’.

Question 6.
Why are the Himalayan rivers perennial ?
Answer:
The Himalayan rivers get the water supply from snow-melt water throughout the year and rainfall in the rainy season. Hence, they are perennial.

Question 7.
Name some tributaries of the river Brahmaputra.
Answer:
Rivers Subanasiri, Kameng, Manas and Sankosh on the right bank. Rivers Buridihang, Dibang, Kapili and Dhansiri on the left bank.

Question 8.
Mention the course of river Narmada.
Answer:
River Narmada rises from the Amarkantak peak of the Mahakal hills from a spring, flows through a rift valley and finally drains into the gulf of Khambat.

Question 9.
Name two rift valleys of India.
Answer:
The valleys of rivers Narmada and Tapti.

Question 10.
What do you mean by an inland river ?
Answer:
A river which has its source from a moutain or highland, flows through the land and finally drains into a lake or other inland water body, is called an inland river. Eg-River Luni of Rajasthan.

Question 11.
Write about the course of river Godavari.
Answer:
The river Godavari (1,465 km) has its source in the Trimbakeswar in the Western Ghats and drains into the Bay of Bengal. Due to its great length, it is often called the Ganga of the south.

Question 12.
What is a lake?
Answer:
A lake is a depression on the surface of the earth filled with natural water coming from rainfall, snow melt, rivers or underground water.

Question 13.
What is a Kayal or lagoon ?
Answer:
A Kayal or lagoon is a water body surrounded by land on three sides and one side connected to the sea. In many cases, sea water may get arrested by sand bars on three sides and form lagoons or kayals. Eg-Chilka lake in Odisha, Vembanad lake in Kerala.

Question 14.
What is a multi-purpose project ?
Answer:
A multi-purpose project is one in which a river is dammed for various purposes like – irrigation, flood control, generation of hydro-electricity, water transport, fisheries, controlling soil erosion, etc.

Question 15.
Which states of India are mostly irrigated by canals ?
Answer:
The states that are mostly irrigated by canals are – Uttar Pradesh, Punjab, Haryana, Rajasthan, West Bengal, Bihar, Andhra Pradesh, Gujarat, etc.

Question 16.
Which states in India are mostly irrigated by tanks ?
Answer:
Most parts of the peninsular India came under tank irrigation. The states predominated by this are – Tamil Nadu, Karnataka, Andhra Pradesh, Madhya Pradesh, Odisha. Apart from these, some areas of West Bengal, Bihar and Gujarat also practice tank irrigation.

Question 17.
What is the advantage of well irrigation ?
Answer:
Wells can be dug very near the fields, so that water can be provided for cultivation very easily.

Question 18.
What is the disadvantage of well irrigation?
Answer:
Wells cannot be dug where the soil is hard or the land is rocky. It is also not possible in areas where water table is very low.

Question 19.
What are inundation canals ?
Answer:
The inundation canals are those which flow during the rainy season when the rivers are in flood.

Question 20.
What are the advantages of canal irrigation?
Answer:
Canals can be divided into branches for reaching water to fields easily. Sometimes the canals can be used for fishing, navigation or other activites.

Question 21.
What are the disadvantages of canal irrigation?
Answer:
Water level in canals may rise or fall according to availability of water in different seasons. Canals cannot be drawn on hard rocky surfaces or sandy deserts.

Question 22.
What do you mean by rain water harvesting ?
Answer:
Rain water harvesting is the accumulation and storage of rain water to reuse rather than allowing it to run off. Its uses include water for gardening, livestock, irrigation, domestic use, etc. It can also be treated and used as drinking water.

Question 23.
Where does the river Indus rise?
Answer:
The river Indus rises in the springs of Sengge Khabab at an altitude of 5,180 m and about 100 km north of Manas Sarovar.

Question 24.
Name the states through which the tributaries of river Indus flow in India.
Answer:
The tributaries of river Indus flow in India through the states of JammuKashmir, Himachal Pradesh and Punjab.

Question 25.
Where does the river Ganga rise from ? What is it known at the source?
Answer:
The river Ganga rises from the Gomukh cave of Gangotri glacier in the Kumaon Himalayas of Uttarakhand. At the source it is known as river Bhagirathi.

Question 26.
Which is the longest river of India ?
Answer:
The longest river of India is river Ganga. It flows through India for 2,071 km out of the total length of 2,510 km.

Question 27.
Where does the river Yamuna rise?
Answer:
The river Yamuna rises from the Yamunotri glacier of Kumaon Himalayas in Uttarakhand. It meets with river Ganga as a right bank tributary in Allahabad.

Question 28.
Which two rivers meet to form river Ganga ?
Answer:
Rivers Bhagirathi and Alokananda meet at the Dev Prayag to form river Ganga.

Question 29.
Why are the Himalayan rivers called Antecedent rivers ?
Answer:
The Himalayan rivers like Ganga, Indus, Brahmaputra existed even before the emergence of the Himalayan mountains. The rise of the mountains have only changed the courses of the rivers. Thus, these rivers are called antecedent rivers.

Question 30.
Name the states thrugh which river Ganga flows in India.
Answer:
The river Ganga flows through Uttarakhand, Uttar Pradesh, Bihar and West Bengal.

Question 31.
Name the states through which river Brahmaputra flows in India.
Answer:
The river Brahmaputra flows through Arunachal Pradesh and Assam in India.

Question 32.
Name four tributaries of river Narmada.
Answer:

• Hiran
• Barna
• Orsang
• Kolar.

Question 33.
Through which states does the river Narmada flow ?
Answer:
The river Narmada flows through Madhya Pradesh and Gujarat.

Question 34.
Name two west flowing rivers of India.
Answer:
Narmada and Tapti.

Question 35.
On which side of the Satpura range is the river Narmada situated ?
Answer:
River Narmada lies to the north of the Satpura range.

Question 36.
Name a famous waterfall on the river Narmada.
Answer:
Dhuandhar waterfalls near Jabalpur in Madhya Pradesh.

Question 37.
Where does river Tapti rise?
Answer:
River Tapti rises from a hot spring called Multai in the Mahadev hills of Madhya Pradesh.

Question 38.
Name four tributaries of river Tapti.
Answer:

• Purna
• Girna
• Bori
• Bheghar.

Question 39.
Which is the highest waterfall of India ?
Answer:
The highest waterfall is the Jog waterfalls on river Sharavati in Karnataka. It is 275 m high.

Question 40.
Mention the course of river Mahanadi.
Answer:
River Mahanadi rises from the Shihawa hills of Rampur district of Chattisgarh and flows into the Bay of Bengal.

Question 41.
Through which states does river Mahanadi flow ?
Answer:
River Mahanadi flows through Chattisgarh and Odisha.

Question 42.
Name two tributaries of river Mahanadi.
Answer:

• River Brahmani
• River Baitarani

Question 43.
Which is the longest river of South India ?
Answer:
The largest as well as the longest river of South India is the river Godavari.

Question 44.
Where does the river Krishna rise?
Answer:
The river Krishna rises in the hills of Mahabaleswar (1,337 m) in the Western Ghats.

Question 45.
Through which states does the river Krishna flow ?
Answer:
River Krishna flows through Maharashtra, Karnataka, Telengana and Andhra Pradesh before meeting the Bay of Bengal.

Question 46.
Which famous dam is built on river Krishna ?
Answer:
The famous dam built on the river krishna is Nagarjuna Sagar Dam.

Question 47.
Name few tributaries of river Krishna.
Answer:
Some tributaries of river Krishna are river Koyna, Bheema, Tungabhadra, Vedavati, Ghat prabha, Musi, Doodh Ganga etc.

Question 48.
Where does the river Cauvery rise?
Answer:
River Cauvery rises in the Brahmagiri hills (1,341 m) of Coorg district of Karnataka.

Question 49.
Name some tributaries of river Cauvery.
Answer:
Some tributaries of river Cauvery are river Himavati, Bedmati, Amaravati, Lakshmana, Tirtha, Simsa, Bhavani etc.

Question 50.
Name the famous waterfalls on river Cauvery.
Answer:
The famous waterfalls on river Cauvery is the Shivasamudram.

Question 51.
Through which states does the river Cauvery flow ?
Answer:
The river Cauvery flows through Karnataka and Tamil Nadu.

Question 52.
Name two famous lakes of Jammu-Kashmir.
Answer:
Dal Lake and Wular lake.

Question 53.
Name two famous lakes of Uttarakhand.
Answer:
Nainital and Bheemtal.

Question 54.
Name two artificial lakes of India.
Answer:

• Osman Sagar in Telengana.
• Pushkar lake in Ajmer district of Rajasthan.

Question 55.
Name four famous irrigation canals constructed in Uttar Pradesh.
Answer:

1. Upper Ganga canal
2. Lower Ganga canal
3. Sarda canal
4. Yamuna canal.

Question 56.
Name four irrigation canals in Punjab.
Answer:

1. Upper Bari Doab canal
2. Sirhind canal
3. Bhakra canal
4. Bist Doab canal.

Question 57.
Name two irrigation canals of West Bengal.
Answer:

• Damodar canal
• Mayurakshi canal.

Question 58.
Which is the largest canal of India ?
Answer:
The largest canal of India is the Indira Gandhi canal or the Rajasthan canal.

Question 59.
Which is the longest canal of India ?
Answer:
The longest canal of India is the Sarda canal of Uttar Pradesh.

Question 60.
Name two perennial canals of India.
Answer:

• Sarda canal of Uttar Pradesh
• Yamuna canal of Punjab.

Question 61.
Which state in India possesses the maximum irrigated land?
Answer:
The maximum irrigated land lies in Punjab. Here, about 94 % of agricultural land is under irrigation.

Question 62.
Which state has the lowest irrigated land in India ?
Answer:
The lowest irrigated land lies in Jammu-Kashmir (only about 1.3 % of total agricultural land).

Question 63.
Which is the longest dam in India ?
Answer:
The longest river dam in India is the Hirakud dam constructed on the river Mahanadi in Odisha.

Question 64.
Which is the highest dam in India ?
Answer:
The highest dam in India is the Bhakra dam constructed on the river Sutlej in Himachal Pradesh.

Question 65.
Which is the largest multipurpose project in India ?
Answer:
The largest multipurpose project in India is the Bhakra-Nangal project on the river Sutlej.

Question 66.
Where has the ‘Sardar Sarovar Project’ been constructed ?
Answer:
The Sardar Sarovar Project has been constructed on river Narmada in Gujarat.

Question 67.
Name the dams constructed under the Damodar Valley Project.
Answer:
The Damodar Valley Project had a plan of constructing 8 dams. But due to lack of funds, only 4 dams could be constructed. These are :

• Maithan
• Panchet
• Konar
• Tilaiya

Question 68.
Name the hydel power stations under the DVC.
Answer:

1. Panchet
2. Maithan
3. Tilaiya

Question 69.
Name the thermal power stations under the DVC.
Answer:

1. Bokaro
2. Durgapur
3. Chandrapura
4. Wariya

Question 70.
Which states lead in irrigation by wells and tubewells?
Answer:
The states of Uttar Pradesh and Rajasthan lead in irrigation by wells and tubewells.

Answer in brief : 3 Marks

Question 1.
Describe the course of the river Indus.
Answer:
The river Indus rises in the springs of Sengge khabab at an altitude of 5,180 m, about 100 km north of Manas Sarovar. It enters Indian territory in Jammu and Kashmir. It flows through Ladakh, Baltistan and Gilgit to finally emerge at of the hills of Atlock. It flows through India for about 709 km, and then enters Pakistan. The main tributaries of Indus in India are – Jhelum, Chenab, Ravi, Beas, Sutlej.

Question 2.
What do you mean by an ‘ideal river’ ?
Answer:
A river which has three distinct courses, that is the upper course in the hilly region, the middle course in the plateau or highland region and the lower course in the plain region is called an ideal river. Eg-River Ganga.

Question 3.
Describe the upper course of the river Ganga.
Answer:
The river Ganga rises from the Gomukh cave of the Gangotri Glacier in the Himalayas. Here it is known as river Bhagirathi. Sweeping westwards for 35 km from Gomukh, the Bhagirathi turns south and flows for another 140 km through the lesser Himalayas. When the Alokananda, originating from the glacial snout of Alakapuri Glacier joins the Bhagirathi at Dev Prayag, it is called the Ganga. From its source at Gomukh till Haridwar, is the upper course of the river Ganga. From Haridwar to the Raj Mahal hills is the middle course, and from the Raj Mahal hills to the Bay of Bengal is the lower course of the river.

Question 4.
Why are the rivers of south India more speedy than the rivers of north India?
Answer:
The rivers of south India, eg-Godavari, Krishna, Cauvery, Tungabhadra, etc. rise from the hills of the peninsula of India and flow through the plateau region before entering the sea. This plateau is made of igneous rocks, which are very resistant and hard to erode. Also, the rivers flow along the slope of the terraces and hills formed due to lava deposition. There is hardly any presence of plains. Hence, the rivers are very speedy.

Question 5.
Why are the south Indian rivers not perennial like the north Indian rivers?
Answer:
The north Indian rivers rise from the snow-clad mountains of the Himalayas. They get their supply of water from snow-melt as well as heavy orographic rainfall that hit the mountains. Hence, they are perennial. The south Indian rivers rise from the lower hills of the plateau region, which are not snow clad. Hence, they receive water only from rainfall. But rainfall does not occur througout the year. The rivers tend to dry up when there is no supply of rain water. Hence, they are non-perennial.

Question 6.
Why does most of the east flowing rivers form deltas?
Answer:
Most of the east flowing rivers form deltas because :

1. The speed of east flowing rivers is less, hence scope of silt deposition is more.
2. Numerous tributaries of these rivers contribute much silt along with water.
3. The continental shelf on the eastem cost is very gentle, which helps in accumulation of silt.
4. The length of the east flowing rivers is much more. Hence, the amount of eroded material is also quite more and the rate of deposition of these materials is also high.

Question 7.
Write a short note on tubewell irrigation.
Answer:
A tubewell is a deep bore dug into the ground with drilling equipments for drawing out ground water with the help of a pump. Tubewells have proved to be very useful in the alluvial plains of Punjab, Haryana, Uttar Pradesh and Bihar. U.P. has the highest number of tubewells. There are about 31,000 tubewells in the country which irrigate about 60 lakh hectares of bud. About 23 % of total irrigated area in India is served by tubewells.

Question 8.
List the advantages and disadvantages of well and tubewell irrigation.
Answer:
Advantages :

• Less costly, hence poor farmers can also afford.
• Water can be drawn out as per requirement.
• Can be constructed very near to the fields.
• The water drawn from underground is rich in minerals, which make it very useful to make the soil fertile.

Disadvantages :

• This kind of irrigation is usually constructed individually, and not in group.
• This can irrigate only a small area.
• Some wells and tubewells may dry up due to use for many years.
• Dependent of level of water in the undergound reservoir.
• Arsenic contamination may result due to overuse of water.

Question 9.
List the advantages of irrigation.
Answer:
The advantages of irrigation are:

• It helps to increase food production.
• It helps to modify the quality of soil.
• It helps to reduce risk of catastrophic damage by droughts.
• It helps to increase national income.
• It increases labour employment and improves the standard of living.
• It provides with the domestic and industrial water supply.
• Sometimes it is used for generation of hydro-electric power.

Question 10.
What are the disadvantages of irrigation?
Answer:
The disadvantages of irrigation are :

• Water logging.
• Rise in salinity or alkalinity of soil.
• Hampers aeration of soil.
• Pollution of underground water.
• Colder and damper climate indirectly caused by irrigation processes cause out break of diseases like malaria.

Question 11.
Discuss the impacts of overusing ground water.
Answer:
The several impacts for overusing ground water are :
(a) Water table may be lowered due to rapid evaporation and drawing out of water.
(b) Wells, ponds etc. may dry up in warm seasons, or due to overdrawing of water.
(c) Too much extraction of ground water creates a partial vacuum which may lead the land surface to collapse.
(d) Too much drawing of water may lead to droughts and soil damage.
(e) Quality of ground water will gradually deteriorate.
(f) Arsenic contamination may result due to drawing of water at very high rates.

Question 12.
What is a watershed ?
Answer:
The highland that separates two adjacent river catchment areas is called a ‘watershed’. They are important because the flow of water in the catchment area, the speed and volume of water, the amount of silt generated, etc. depend on the nature of the watershed.

Question 13.
Why is tubewell irrigation popular in north India ?
Answer:
Tubewell irrigation is popular in north India because :

1. The lndo-Gangetic plain is composed of soft porous sedimentary rocks which can be dug easily.
2. The porous layers of the rocks allow recharge of groudwater easily, hence water is easily available in tubewells dug in this region.
3. The water table in this region is near the surface, thus it can be acquired by minimum digging.
4. Tubewells are less expensive to construct than canals and other means of irrigation.

Question 14.
What are the advantages of rain water harvesting ?
Answer:
The advantages of rain water harvesting are :

1. It provides an independent water supply during regional water restrictions or droughts.
2. It can mitigate flooding of low lands.
3. It helps to sustain groundwater level.
4. It ensures availability of potable water, clean and free from salinity.
5. It helps to re-use runoff water for gardening, livestock, irrigation, domestic use, etc.

Question 15.
Why are rivers Narmada and Tapti west flowing ?
Answer:
The rivers Narmada and Tapti are west flowing because :

1. The slope of the land over which these rivers flow is from east to west.
2. The Western Ghats do not exist in the region where these rivers flow. Hence, they meet the Gulf of Khambat without any hurdles.
3. These rivers flow through rift valleys. Hence, they have made their way through the narrow valleys along the fault lines very easily.

Question 16.
Why don’t the west-flowing rivers form deltas before meeting the sea?
Answer:
The west-flowing rivers of India, i.e. Narmada and Tapti do not form deltas at their mouths because :

1. Length : The rivers flow for a short length and do not have enough water or amount of load. (Narmada – 1312 km, Tapti – 928 km)
2. Tributaries : These rivers have a very few tributaries. Hence, contribution of load is also very less.
3. Type of rock : The rivers flow over hard rocky surface. Hence, amount of eroded material is small.
4. Speed : The rivers flow with great speed, thus removing and discarding all the load far away from the mouths.
5. Continental shelf: The continental shelf in the region where the rivers meet the Gulf of Khambat is quite steep. Thus, accumulation of silt to form deltas is difficult.

Question 17.
Differentiate between Wells and Tubewells.
Answer:

Wells	Tubewells
i. Wells are dug in soft soil and water is pulled out by hand or with the help of animals.	i. Tubewells are constructed by inserting metal or nylon pipes in soft soil and pulling out water by pumps.
ii. Help to pull out water from shallow levels.	ii. Help to pull out water from deep levels.
iii. No requirement of electric or other power resources.	iii. Cannot work without using power from petrol, diesel, electricity etc.
iv. Radius of well is large.	iv. Radius of pipeline is very small.
v. The mouth of the well remains open.	v. The mouth of the pipe remains in the pump.

Question 18.
Mention the states where canal irrigation is predominant.
Answer:
Canal irrigation is predominant in – Uttar Pradesh, Punjab, Haryana, Rajasthan, West Bengal, Bihar, Andhra Pradesh, Gujarat etc.

Question 19.
Differentiate between inundation canals and perennial canals.
Answer:

Inundation canals	Perennial canals
i. In rainy season, the excess water of the rivers is diverted for imigation and other works through canals.	i. Water from perennial rivers is used for irrigation and other purposes throughout the year.
ii. Usually usable in rainy season and remain dry in dry season.	ii. Usually usable in all seasons throughout the year.
iii. Usually seen in flood-prone areas.	iii. Usually seen in areas where perennial rivers flow.
iv. Usually constructed in the delta regions or lower courses of rivers.	iv. Usually constructed in the middle course or the plain lands of a river.
v. Helps in flood control.	v. No remarkable influence in flood control.

Question 20.
What is a Multi-purpose river project? What are its aims?
Answer:
A project on a river that is planned for economic and social development of a place by using the water of the river for multiple purposes, is called a multipurpose project.
Aims – The different aims of a multi-purpose project are – (i) Irrigation, (ii) Production of hydro-electric power, (iii) Flood control, (iv) Navigation and water transport, (v) Supply of drinking water, (vi) Pisciculture, (vii) Building of bridges, (viii) Construction of roadways and railways, (ix) Scope of employment to a huge population, (\mathrm{x) Control of soil erosion, (xi) Development of tourist spots, (xii) Afforestation, (xiii) Development of new settlements.

Answer in details : 5 Marks

Question 1.
Describe the course of river Ganga.
Answer:
Ganga is the main and longest river of India. Its total length is 2,510 km, of which 2,071 km flows through India.

Upper course : The river Ganga rises from the glacial snout Gomukh of the Gangotri glacier. It is then called Bhagirathi. It meets with river Alokananda at the Dev Prayag, after which the river comes to be known as the Ganga. The upper course of Ganga extends from Gomukh to Haridwar for about 320 km. Middle course : It stretches from Haridwar to Dhulian in West Bengal. The left bank tributaries are Ram Ganga, Gomoti, Ghaghra, Gandak, Kosi, etc. The right bank tributaries are – Yamuna and Son. Yamuna is the largest and most important tributary of the Ganga.

Lower course : The lower course extends from Dhulian in Murshidabad (WB) to the Bay of Bengal. The river divides into two branches near Giriya district of Mushidabad as Bhagirathi and Padma. The Padma enters Bangladesh and meets the Bay of Bengal from there. The Bhagirathi flows southwards through West Bengal as Hooghly river. The main left bank tributaries are – Jalangi, Ichhamati, Churni, etc. The right bank tributaries are – Brahmani, Dwarka, Ajay, Mayurakshi, Damodar, Rupnarayan, Kangsabati, etc. The Bhagirathi Hooghly, along with the Padma, form the world’s largest delta before meeting the Bay of Bengal.

Question 2.
Describe the course of river Brahmaputra.
Answer:
The Brahmaputra river is 2700 km long, of which 885 km flows through India. It rises from the Chemayundung glacier, south west of Manas Sarovar. It flows eastward through Tibet where it is known as Tsang-Po. After taking a sharp bend towards the south, it enters India through a deep gorge in the east of Namcha Barwa in Arunachal Pradesh as Dihang. The river Dihang meets with rivers Dibang and Lohit and then flow as a single river called Brahmaputra. It flows through Assam from the east near Sadiya to the west upto Dhubri and then takes a sharp turn towards the south and enters Bangladesh as river Yamuna. The important right bank tributaries are-Subansiri, Barali, Manas, Teesta, etc. The left bank tributaries are – Buri, Dihing, South Dhansiri, etc.

Question 3.
Discuss the importances of lakes, canals and reservoirs in human life.
Answer:
The importances of lakes, canals and reservoirs in human life are –
i. Irrigation : Lake water can be used for irrigation and make cultivation possible in adjacent areas.

ii. Flood control : Lakes and reservoirs help to hold the excess runoff from rain water and help to control floods.
iii. Fishing : The water bodies help in cultivation of fish and ensure supply of protein based food to the locality as well as outside.
iv. Transport : Large lakes may act as a mode of transport by boats and steamers.
v. Tourism : Beautiful scenery and pleasant weather near lakes and resevoirs attract many tourists, thus gain econonic importance as tourist spots.

Question 4.
What is the impact of overuse of ground water?
Answer:
The biggest reservoir of fresh water on earth is ‘ground water’ which holds more than 20 times of total surface water (lakes, rivers, ponds, etc.). Ground water is pumped out to meet agricultural, industrial and domestic depends. But overuse of ground water may cause several problems –

1. Lowering of water table.
2. Drying up of wells, ponds, etc.
3. Subsidence and collapse of land surface.
4. Drought and damaged soil.
5. Deterioration of water quality.

In India, over 16 % of ground water resources are over exploited, mainly in north western, western and peninsular regions. If this trend continues, 60 % of India’s acquifers will be in critical condiions in coming 20 years.

Question 5.
Write a short note on the Damoder Valley Project.
Answer:
The Damodar Valley Project is the first Multi-purpose project in independent India. It was started in 1948. It was based on the Tennessee Valley Project of USA. The Damodar Valley Corporation (DVC) has been developed on river Damodar in Jharkhand and West Bengal. It consists of a series of dam on this river and its tributaries. The river Damodar rising in the chotanagpur plateau region, fluctuates in water level too much. In the rainy season it causes dreadful floods destroying life and property. Hence, it is known as the ‘Sorrow of Jharkhand (Bihar)’.

The DVC has constructed multi-purpose dams at Tilaiya (on river Barakar), Konar (on river Konar), Maithon (on river Barakar) and Panchet (on river Damodar). Hydel power stations have been constructed at Maithan, Tilaiya and Panchet. The 672 m long and 11.58 m deep barrage on the river Damodar at Durgapur, 226 km long irrigation canals help to irrigate about 5 lakh hectares of land. The thermal power stations at Bokaro, Chandrapura, and Durgapur produce about 1,081 MW of electricity. The DVC has now handed over its overall control to the Govt. of West Bengal.

Question 6.
What is Watershed management?
Answer:
Watershed management refers to the scientific use and utilisation of water recources to stop soil erosion, increase soil fertility, control floods, prevent siltation of river beds and maintain proper land use patterns. The various methods that are used in watershed management are –
i. Slope management : The higher slopes of the river basin that are prone to land slides and soil erosion can be taken care of by planting trees, grasslands, stopping jhum cultivation. Guard walls can be built in some cases to protect the land.
ii. Flood control : Floods can be controlled by dredging of rivers, ponds, lakes etc and increasing their water holding capacities.
iii. Gully erosion : Gully erosion and sheet erosion can be controlled by planting trees across the flow of runoff and building small dams at places.
iv. Contour farmıng : Contour farming, terrace farming etc. can help to stop soil erosion and increase water seepage to increase the ground water level.
v. Multi-purpose projects : Multi-purpose projects can be planned for purposes like irrigation, hydel power, fish culture, flood control, water transport, control of soil erosion, tourism, etc.

Question 7.
Discuss about rain water harvesting in Tamil Nadu.
Answer:
Rain water harvesting is the accumulation and storage of rain water for reuse, rather than allowing it to run off. Its uses include water for gardening, livestock, irrigation, domestic use, etc. It can also be used as drinking water.

Tamil Nadu : Tamil Nadu receives rainfall twice a year. Hence, it is the best region for rain water harvesting. In order to augment ground water resourses, it has been made mandatory in Tamil Nadu to provide rain water harvesting structures in all buildings. The arrangement is such deviced that after the first rain washes away the dirt and dust of the roofs, water can be collected and stored. Different type of devices are used for different types of roofs. Presently, 40 % of rain water is being stored underground. In Chennai alone, a 150 \mathrm{sq . \mathrm{km underground water reservoir meets the scarcity of water.

Question 8.
Describe canal irrigation system in India.
Answer:
The method of irrigation by digging canals from rivers towards agricultural fields through the soft silty soil is known as canal irrigation. Canal irrigation is popular in plains where the slope of land is moderate.
Areas – The areas under canal irrigation in India are Punjab, Uttar Pradesh, Delta regions of rivers, etc.
Types – Canals are usually of two types –
(i) Perennial canals – Which have water throughout the year as they are dug from perennial rivers.
(ii) Inundation canals – Which receive water when the rivers are in flood in rainy season.
Amount of canal irrigation – About 50 % of canals are spread over Uttar Pradesh, Punjab, Haryana, West Bengal and Andhra Pradesh. About 38 % of agricultural land is irrigated by canals.

Question 9.
What is rain water harvesting ? What are the different methods of rain water harvesting ?
Answer:
The process of collecting rain water from roof tops and other open places for reuse for different purposes is called rain water harvesting.
The different methods of rain water harvesting are –
i. Construction of tanks – Rain water can be collected in natural or artificial tanks, ponds, lakes, etc. in the rainy season and can be used later in the dry season.

ii. Construction of Small dams – Higher dams disrupt the natural flow of water in the rivers to a great extent. This may cause many adverse effects. But construction of small and low dams to stop the flowing water only by portions may come out to be a very useful method of rain water harvest.

iii. Collection of rain water – Rain water can be collected from roof tops and other open surfaces or areas which receive heavy rainfall from the monsoons.

iv. Proper use of ground water – The ground water utilisation may be improved from 35-40 % to 60 % by implementing proper methods of acquiring the ground water. Unplanned water acquiring processes must be prevented with the help of rules and regulations.

v. Ground water recharge – Scope must be given for percolation of rain water into the soil for recharge of underground water. In some cases, there may be the need for recharging ground water artificially.

Multiple Choice Questions (MCQ) : 1 Mark

Question 1.
Which of the following is a Trans-Himalayan river?
(A) Ganga
(B) Yamuna
(C) Sutlej
(D) Ravi
Answer:
(C) Sutlej

Question 2.
Which of the following rivers is not a tributary of Ganga ?
(A) Gomati
(B) Gandak
(C) Kosi
(D) Ghagra
Answer:
(D) Ghagra

Question 3.
Which of the following rivers lies in a rift valley ?
(A) Luni
(B) Chambal
(C) Sone
(D) Tapti
Answer:
(D) Tapti

Question 4.
Narmada originates from its source situated in the state of :
(A) Maharashtra
(B) Uttar Pradesh
(C) Madhya Pradesh
(D) Andhra Pradesh
Answer:
(C) Madhya Pradesh

Question 5.
The Jog falls are situated on the :
(A) Tapti river
(B) Sharavati river
(C) Cauvery river
(D) Bhima river
Answer:
(B) Sharavati river

Question 6.
Why is the Delta of the Indus small compared to the Delta of the Ganga?
(A) The Indus traverses a shorter distance than the Ganga
(B) The Indus is not as broad as the Ganga
(C) The path of the Indus is through arid area while the Ganga collects more water along its path to the sea
(D) None of the above
Answer:
(C) The path of the Indus is through arid area while the Ganga collects more water along its path to the sea

Question 7.
The Indian rivers of the Indus Basin are :
(A) Sutlej, Beas and Ravi
(B) Ganga, Beas and Sutlej
(C) Betwa, Sone and Kosi
(D) Gomati, Kosi, Gandak
Answer:
(A) Sutlej, Beas and Ravi

Question 8.
Beas flows through the State of –
(A) Punjab, Haryana and Rajasthan
(B) Punjab, Haryana and Jammu
(C) Punjab and Himachal Pradesh
(D) Punjab and Haryana
Answer:
(D) Punjab and Haryana

Question 9.
River Cauveri flows through the States of-
(A) Madhya Pradesh, Maharashtra and Tamil Nadu
(B) Karnataka, Kerala and Tamil Nadu
(C) Madhya Pradesh, Gujarat and Tamil Nadu
(D) Kerala, Karnataka and Andhra Pradesh
Answer:
(B) Karnataka, Kerala and Tamil Nadu

Question 10.
Ganga beyond Farakka, when it enters Bangladesh, is known as :
(A) Padma
(B) Meghna
(C) Hooghly
(D) Swaran Ganga
Answer:
(A) Padma

Question 11.
Which of the following has almost the same point of beginning ?
(A) Ganga and Indus
(B) Ganga and Brahmaputra
(C) Beas and Tapti
(D) Indus and Brahmaputra
Answer:
(D) Indus and Brahmaputra

Question 12.
The river that flows between the Vindya and the Satpura Mountain is :
(A) Maki
(B) Narmada
(C) Tapti
(D) Sharavati
Answer:
(B) Narmada

Question 13.
The Alakananda and the Bhagirathi meet at :
(A) Prayag
(B) Devaprayag
(C) Haridwar
(D) Rishikesh
Answer:
(B) Devaprayag

Question 14.
The left bank tributary of the Ganga is the :
(A) Sone
(B) Gomati
(C) Yamuna
(D) Damodar
Answer:
(B) Gomati

Question 15.
The river Chambal flows into the :
(A) Tapi
(B) Ganga
(C) Yamuna
(D) Narmada
Answer:
(C) Yamuna

Question 16.
The name “The Gift of the Indus” is given to :
(A) U.P
(B) Gujarat
(C) Sindh
(D) Rajasthan
Answer:
(C) Sindh

Question 17.
Tapti flows into the :
(A) Arabian sea
(B) Cambay Gulf
(C) Gulf of Kutch
(D) All of these
Answer:
(B) Cambay Gulf

Question 18.
The town situated at the mouth of the river Tapti is :
(A) Surat
(B) Broach
(C) Honnavar
(D) Joypur
Answer:
(A) Surat

Question 19.
Jog Falls is across the river:
(A) Sharavati
(B) Cauvery
(C) Krishna
(D) Godavari
Answer:
(A) Sharavati

Question 20.
The source of Godavari is :
(A) Amarkantak
(B) Triambak
(C) Mahabaleswar
(D) Nasik
Answer:
(B) Triambak

Question 21.
Machalipatnam is located at the mouth of :
(A) Tapi
(B) Cauvery
(C) Krishna
(D) Godavari
Answer:
(C) Krishna

Question 22.
The main tributary of the Cauvery is the :
(A) Parna
(B) Vennan
(C) Vettar
(D) Coleroom
Answer:
(D) Coleroom

Question 23.
Porunai is another name of the :
(A) Ganga
(B) Cauvery
(C) Vaighi
(D) Tamiraparani
Answer:
(D) Tamiraparani

Question 24.
The Vaigai river rises in the :
(A) Coorg
(B) Agastiya Hills
(C) Cardamom Hills
(D) Anaimudi
Answer:
(C) Cardamom Hills

Question 25.
The dam across Periyar is at :
(A) Amaravati
(B) Thekkady
(C) Palani
(D) Krishna
Answer:
(B) Thekkady

Question 26.
Tungabhadra flows into the river:
(A) Godavari
(B) Cauvery
(C) Palani
(D) Krishna
Answer:
(D) Krishna

Question 27.
Important west flowing river is :
(A) Mahanadi
(B) Cauvery
(C) Krishna
(D) Narmada
Answer:
(D) Narmada

Question 28.
Bhakra-Nangal is a …… project.
(A) multipurpose
(B) power
(C) irrigation
(D) none
Answer:
(A) multipurpose

Question 29.
Mettur is the most important multipurpose project for the state of :
(A) Kerala
(B) Karnataka
(C) Andhra Pradesh
(D) Tamil Nadu
Answer:
(D) Tamil Nadu

Question 30.
Kosi Project is a joint venture of :
(A) India and Bangladesh
(B) India and Nepal
(C) India and Bhutan
(D) Bhutan and Nepal
Answer:
(B) India and Nepal

Question 31.
Sivasamudram fall is across river :
(A) Godavari
(B) Krishna
(C) Sharavati
(D) Cauvery
Answer:
(D) Cauvery

Question 32.
The Ganga enters the great plains at :
(A) Agra
(B) Allahabad
(C) Patna
(D) Haridwar
Answer:
(D) Haridwar

Question 33.
The peninsular rivers have their source in the :
(A) Satpura
(B) Western Ghats
(C) Himalayas
(D) Bay of Bengal
Answer:
(B) Western Ghats

Question 34.
The most important tributary of the Ganga is :
(A) Tapti
(B) Yamuna
(C) Periyar
(D) None of these
Answer:
(B) Yamuna

Question 35.
The rivers Narmada and Tapti flow into the Gulf of :
(A) Bay of Bengal
(B) Kutch
(C) Mannar
(D) Khambhat
Answer:
(D) Khambhat

Question 36.
The Yamuna joins the Ganga at :
(A) Delhi
(B) Haridwar
(C) Allahabad
(D) Calcutta
Answer:
(C) Allahabad

Question 37.
The northern channel of Cauvery is called :
(A) Hemavathi
(B) Coleroom
(C) Bhavani
(D) Son
Answer:
(B) Coleroom

Question 38.
The river Krishna enters the Bay of Bengal near :
(A) Hyderabad
(B) Vijayawada
(C) Masulipatnam
(D) Nellore
Answer:
(B) Vijayawada

Question 39.
The biggest artificial reservoir is :
(A) Nijam Sagar
(B) Govind Vallab Pant Sagar
(C) Stanley Reservoir
(D) Govind Sagar Lake
Answer:
(B) Govind Vallab Pant Sagar

Question 40.
Rihand Project is mainly a ….. project :
(A) Drinking
(B) Irrigation
(C) Power
(D) Multipurpose
Answer:
(D) Multipurpose

Question 41.
This flows through a rift valley :
(A) Ganga
(B) Mahanadi
(C) Tapti
(D) Luni
Answer:
(C) Tapti

Question 42.
A dam is located at Sambalpur on the Mahanadi river :
(A) Damodar
(B) Bhakra
(C) Hirakud
(D) Nagarjuna Sagar
Answer:
(C) Hirakud

Question 43.
River Damodar is a tributary of :
(A) Yamuna
(B) Sabarmati
(C) Ganga
(D) Ajoy
Answer:
(C) Ganga

Fill in the blanks : 1 Mark

1. The Ganga river comes from the Gangotri glacier which is located at a height of ________ m. in the north of the Kedarnath peak.
2. The river Ganga carries about ________ of the water of the total drainage of India.
3. The river ganga meets river ________ near Gaalundo.
4. Most of the drainage of Himalayas is ________ .
5. The river Gomti meets the river Ganga near ________ .
6. The river ________ flows in India, Bangladesh and Tibet.
7. The ________ waterfalls lie in the upper course of the river Narmada.
8. The ________ lake in India has the highest salinity.
9. The river Brahmaputra is known as ________ in Tibet.
10. The river ________ changes its course frequently
Answer:
1. 6600
2. 25 %
3. Brahmaputra
4. Antecedent
5. Gazipur
6. Brahmaputra
7. Kapil dhara
8. Sambhar
9. Tsang po
10. Kosi

State True or False : 1 Mark

1. About 15 % of the agricultural fields in India are irrigated with the help of wells. [ ]
2. Rajasthan ranks first in India in well and tube well irrigation. [ ]
3. The Bhakra-Nangal multipurpose project has been constructed on the river Krishna. [ ]
4. The Hirakud dam has been constructed on the river Mahanadi. [ ]
5. The Bhakra-Nangal project is the longest multipurpose project of India [ ]
6. The Koleru lake is the largest sweet water lake in India. [ ]
7. The Pangong lake is the highest lake of the world. [ ]
8. The largest lake of western India is the Loktak lake. [ ]
9. Pulicat lake is the largest lake of Kerala. [ ]
10. The Wular lake is a salt water lake. [ ]
Answer:
1. True
2. False
3. False
4. True
5. True
6. True
7. True
8. False
9. False
10. False

Match the following : 1 Mark

List I (Rivers)	List II (Tributaries)
A. Indus	1. Mahananda
B. Ganga	2. Bhima
C. Krishna	3. Wainganga
D. Godavari	4. Nubra

Answer:

List I (Rivers)	List II (Tributaries)
A. Indus	4. Nubra
B. Ganga	1. Mahananda
C. Krishna	2. Bhima
D. Godavari	3. Wainganga

Answer in few words : 1 Mark

Question 1.
Where does the river Indus rise?
Answer:
From the springs of Sengge Khabab, 5,180m high, 100 km north of Manas Sarovar.

Question 2.
Name some Himalayan tributaries of Indus.
Answer:
Gantang, Zaskar, Dras, Shyok, Shigar, etc.

Question 3.
Where does the river Sutlej rise?
Answer:
In lake Rakas in Tibet, 4,555 m high.

Question 4.
Where does the river Beas rise?
Ins.
Beas kend near Rohtang Pass at an elevation of 4,361 m.

Question 5.
Where does the river Ravi rise?
Answer:
From the Kulu hills near Rohtang pass.

Question 6.
How does the river Chenab rise?
Answer:
Formed by union of two streams, the Chandra and the Bhaga.

Question 7.
Where does the river Jhelum rise?
Answer:
From a spring at Verinag in the south-eastern part of the vale of Srinagar.

Question 8.
How muh area does the Ganga basin cover of the total land surface of India?
Answer:
25 %

Question 9.
Where does the river Ganga rise ?
Answer:
Gomukh cave of Gangotri glacier.

Question 10.
What is the source of river Alakananda?
Answer:
Alakapuri Glacier.

Question 11.
Which two rivers meet at Devaprayag ?
Answer:
Alakanada and Bhagirathi, forming river Ganga.

Question 12.
Which two rivers meet at the Rudraprayag ?
Answer:
Alakananda and Mandakini.

Question 13.
How far does the upper course of Ganga extend?
Answer:
Gangotri glacier to Haridwar.

Question 14.
How far does the middle course of Ganga extend?
Answer:
Haridwar to Raj Mahal hills.

Question 15.
How far does the lower course of Ganga extend?
Answer:
Raj Mahal hills to the Bay of Bengal.

Question 16.
Name an ideal river of India.
Answer:
River Ganga.

Question 17.
Name the largest tributary of river Ganga.
Answer:
River Yamuna.

Question 18.
Where does river Yamuna rise ?
Answer:
Yamunotri glacier.

Question 19.
Where does river Yamuna meet river Ganga ?
Answer:
At Sangam in Allahabad.

Question 20.
Name some tributaries of Yamuna on the right bank.
Answer:
Chambal, Sindh, Betwa, Ken.

Question 21.
Where does river Kosi rise?
Answer:
From the Tibet plateau.

Question 22.
Which river is called the Sorrow of Bihar?
Answer:
River Kosi.

Question 23.
Where is the source of river Brahmaputra ?
Answer:
Chemayundung glacier south-west of Manas Sarovar.

Question 24.
What is river Brahmaputra known as in Tibet ?
Answer:
River Tsangpo.

Question 25.
Which two rivers meet to form river Brahmaputra.
Answer:
Rivers Dihang and Dibang.

Question 26.
Name an inland river of India.
Answer:
River Luni of Rajasthan.

Question 27.
Name the west flowing rivers of peninsular India.
Answer:
Rivers Narmada and Tapti.

Question 28.
Where does river Narmada rise from ?
Answer:
Amarkantak Peak of the Mahakal Range.

Question 29.
Where does river Tapti rise from?
Answer:
Mahadeo hills.

Question 30.
Where does the river Tapti drain its water finally?
Answer:
Gulf of Khambat.

Question 31.
Where is the source of river Mahanadi ?
Answer:
Near Amarkantak Peak of the Mahakal range.

Question 32.
Name the main tributaries of river Mahanadi.
Answer:
Rivers Brahmani and Baitarani.

Question 33.
Name the longest river of peninsular India.
Answer:
River Godavari.

Question 34.
What is river Godavari also known as ?
Answer:
The Ganga of the south.

Question 35.
Where is the source of river Krishna?
Answer:
Mahabaleshwar hills.

Question 36.
Name the major tributaries of river Krishna.
Answer:
Rivers Bhima and Tungabhadra.

Question 37.
Where is the source of river Cauvery ?
Answer:
Brahmagiri hills of Westem Ghats.

Question 38.
Name the main tributaries of river Cauvery.
Answer:
Rivers Himavati, Bhavani, Bedavati, Shimsa.

Question 39.
Name the famous waterfalls on river Cauvery.
Answer:
Shivasamudram.

Question 40.
Name 2 kayals or lakes of Kerala.
Answer:
Vembanad (largest) and Ashtamudi.

Question 41.
Name 2 lakes of Jammu and Kashmir.
Answer:
Dal lake, Wular lake.

Question 42.
Name 2 lakes of Uttarakhand.
Answer:
Bheemtal and Nainital.

Question 43.
Name 2 artificial lakes of India.
Answer:
Osman Sagar of Telengana, Puskar lakes of Rajasthan.

Question 44.
Name two irrigation canals of West Bengal.
Answer:
Damodar canal, Mayurakshee canal.

Question 45.
Name the largest irrigation canal of India.
Answer:
The Indira Gandhi canal or the Rajasthan canal.

Question 46.
Which is the longest canal of India ?
Answer:
Sharada canal of Uttar Pradesh.

Question 47.
Name an inundation canal of India.
Answer:
Hijli canal of West Bengal.

Question 48.
Name two perennial canals of India.
Answer:
Sharada canal of UP, Damodor canal of West Bengal.

Question 49.
Which state of India is maximum irrigated ?
Answer:
Punjab (about 94 % of cultivated land).

Question 50.
Which is the longest river dam of India ?
Answer:
Hirakud dam on river Mahandi in Odisha.

Question 51.
Name the highest dam of India.
Answer:
Bhakra Nangal dam on river Sutlej in Punjab.

Question 52.
Name the largest multipurpose project of India.
Answer:
Bhakra-Nangal Project.

Question 53.
Where is the ‘Sardar Sarovar Project’ located ?
Answer:
On river Narmada in Gujarat.

Question 54.
Name the dams under Damodar Valley Corporation.
Answer:

1. Mythan
2. Panchet
3. Konar
4. Tilaiya.

Question 55.
Which state ranks first in use of wells and tubewells for irrigation?
Answer:
Uttar Pradesh.

Question 56.
Which state ranks first in rain water harvesting ?
Answer:
Tamil Nadu.

Question 57.
Which region is apt for digging wells for irrigation?
Answer:
Regions with soft soil and ample of ground water.

Question 58.
How much area is under canal irrigation in India ?
Answer:
45 % of total irrigated area.

Question 59.
On which river is the Mythan dam constructed?
Answer:
River Barakar.

Question 60.
On which river is the Panchet dam constructed?
Answer:
River Damodar.

Detailed explanations in West Bengal Board Class 10 Geography Book Solutions Chapter 5.2 Physiography of India offer valuable context and analysis.

WBBSE Class 10 Geography Chapter 5.2 Question Answer – Physiography of India

Answer in short : 2 Marks

Question 1.
What is the east west extention of the Himalaya.
Answer:
The Himalayas extent from Nanga Parbat in Jammu Kashmir in the West to the Namcha Barwa of Arunachal Pradesh in the east.

Question 2.
Name some famous peaks of the Himalayas.
Answer:
Mt. Everest ( 8,848 m), Kanchenjunga (8,598 m) Dhaulagiri (8,172 m), Nanga Parbat (8,126 m), Annapurna (8,076 m), Nandadevi (7,817 m) etc.

Question 3.
What are ‘doons’?
Answer:
Broad longitudinal valleys lying between the main Himalayas and the Shiwalik range formed by deposition of materials brought down by Himalayan rivers, are called ‘doons’. Eg- Dehradun.

Question 4.
What is the Deccan Trap?
Answer:
The Deccan plateau which is composed of sheets of lava forming basalt rocks descends from west to east like stairs step by step, near the Maharashtra plateau. This region is called the Deccan Trap. [Trap = ‘Steps’ in Swedish]

Question 5.
What is the Rann of Kachch ?
Answer:
The western coastal region spreading through the Kutch peninsula of Gujarat is a low marshy land full of salt deposition due to submergence into the adjacent sea. This region is known as the Rann of Kutch. The northern part is known as the Greater Rann and the southern part is known as the Lesser or Smaller Rann. A few hillocks and isolated rocks can be seen in the Rann of Kutch.

Question 6.
Write a short note on the Western Himalaya.
Answer:
The Western Himalaya lie to the extreme west of the chain of the Himalayan mountains. They are further subdivided into – (i) The North Kashmir Himalaya. (ii) The South Kashmir Himalaya, (iii) The Himachal Himalaya, (iv) The Uttaranchal Himalaya. The Kashmir Himalaya is further divided into the Ladakh range, Zanskar range and the Pir Panjal range. Ladakh is the highest plateau of the world, that lies within these ranges. The important mountain passes present here are – Zojila pass between Srinagar and Leh, and Shipki-la on the Indo-China border.

Question 7.
Write the extent of the northern plains of India.
Answer:

The northern plains of India lie to the south of the Himalayas. It extends from the eastern Rajasthan plains in the west to the Brahmaputra valley in the east for a distance of about 2,500 km. They are 145-480 km broad. They are also known as The Great Northern Plains.

Question 8.
Describe the Punjab-Haryana Plains of the Indus basin.
Answer:
The Punjab-Haryana Plains of the Indus basin are drained by the tributaries of river Indus, i.e. Ravi, Beas and Sutlej. These are flat plains with an average elevation of 200-240 m. These fertile plains include the Bari Doab (between Ravi and Beas rivers) and Bisht Doab (between Beas and Sutlej rivers)

Question 9.
What is Khadar?
Answer:
The lowlands formed in the lower course of the river Ganga and its tributaries, by the deposition of detritus of new alluvium in the river beds and adjacent areas is called Khadar.

Question 10.
What is Bhangar?
Answer:
The uplands formed on the western side of the Ganga plains due to deposition of older alluvium which are coarse and grannular, is known as Bhangar.

Question 11.
What is Malnad?
Answer:
The Western part of the Karnataka plateau which is 320 km long and 35 km wide, is highly dissected and have deeply cut valleys. This region is known as the Malnad.

Question 12.
What is Maidan?
Answer:
The eastern part of the karnataka plateau is formed of rolling plains with low granite hills. This region is known as the Maidan.

Question 13.
Name the important passes in the Western Ghats.
Answer:
The important passes in the Western Ghats are: Thal Ghat, Bhor Ghat and Pal Ghat.

Question 14.
Describe the Eastern Ghats.
Answer:
The Eastern Ghats form the eastern edge of the Deccan Plateau. They are lower in height than the Western Ghats. The Mahendragiri (1,501 m) in Odisha is the highest peak of these hills. The Eastern Ghats have been highly eroded by rivers flowing towards the Bay of Bengal and have been lowered to plains.

Question 15.
Classify the Western Coastal Plains.
Answer:
The Western Coastal Plain is divided into several parts – it is known as the Konkan Coast in Maharashtra, the Karnataka Coast in Karnataka and the Malabar Coast in Kerala. The Gujarat plain is the broadest part of the western coastal plains.

Question 16.
Write about the islands of India.
Answer:
There are two major groups of islands in India. (a) The Andaman and Nicobar Islands : They are located in the Bay of Bengal. They are a group of 324 islands. Saddle Peak (750 m) in North Andaman is the highest peak in this region. Barren island is the only active volcano of India. (b) Lakshadweep : This is a group of islands in the Arabian sea, mainly made up of coral depositions.

Question 17.
Why is India called a miniature edition of the world ?
Answer:
India is a large continent with a great variety in topography. Almost all kinds of relief regions are found here. Numerous type of climates are also found here. There is a great variety of cultural traits as well. Thus, it is rightly called a miniature edition of the world.

Question 18.
Where is the Ladakh plateau located?
Answer:
The Ladakh plateau lies to the North-East of the Ladakh range (between the rivers Indus and Sayak). This is the highest plateau of India.

Question 19.
How can the Himalaya be divided according to its breadth ?
Answer:
The Himalaya is divided according to its breadth from south to north(i) Siwalik (ii) Himachal (iii) Himadri (iv) Tethys.

Question 20.
What is the Siwalik?
Answer:
The Siwalik is the southernmost range of the Himalaya. This is made up of smaller mountains running from west to east. It is 2400 km long and 10-15 km wide.

Question 21.
How is the Himalaya classified along its length ?
Answer:
Along its length, the Himalaya is classified as – (i) Western Himalaya (ii) Central Himalaya (iii) Eastern Himalaya.

Question 22.
Write a short note on the Kashmir valley.
Answer:
The Kashmir Valley lies in Kashmir. It is 150 km long, 80 km wide and covers an area of 4,865 sq . km. This valley comprises great snow clad mountains, the Dal and Wular lakes and tremendous scenic beauty. The valley has depositions of materials brought down by river and glacial erosion. These silt depositions are locally known as Karewa, and are famous for saffron cultivation. The river Jhelum flows through the Karewa.

Question 23.
What do you mean by the Syntaxial bend of the Himalaya ?
Answer:
The chain of Himalayan mountains run East-West in general. But they seem to take bends drastically at the western and eastern corners and turn southwards. These bends are known as the Syntaxial bends. The western syntaxial bend lies near the deep gorge created by river Indus near the Nanga Parvat. The eastern syntaxial bend lies in Arunachal Pradesh, where the mountains take a hair-pin turn after crossing the river Brahmaputra.

Question 24.
Write a short note on the Meghalaya plateau.
Answer:
The Meghalaya plateau comprises the Garo, Khasi, Jayantia and Mikir hilly regions of Meghalaya. It is also known as the Shillong plateau. It is actually a part of the Chotanagpur plateau. In historic times, a huge portion of the huge plateau region subsided and resulted in the formation of the dissected plateau of Meghalaya.

Question 25.
What is a ‘Dhrian’?
Answer:
In Rajasthan, the moving sand dunes of the Thar desert are called ‘Dhrians’.

Question 26.
What is a ‘Dhand’?
Answer:
In Rajasthan, in the Thar desert, the huge and deep hollows or depressions created by deflation of sand by wind, are called ‘Dhands’. These are also called the dry lakes.

Question 27.
What is a ‘Thali’?
Answer:
In the Thar desert in Rajasthan, the fixed or immobile sand dunes are called ‘Thalis’.

Question 28.
What is a Kayal ?
Answer:
In the Malabar coast, due to numerous earth movements, land has been submerged and raised above sea level for a number of times. This has led to the formation of several low-lying regions that remain submerged in sea water. These are called backwaters, lagoons or Kayals. The Vembanad Kayal is the largest Kayal in India.

Question 29.
What is the ‘Bagri’ ?
Answer:
‘Bagri’ is the dead part of the delta of river Ganga, where no silt deposition is currently taking place. It comprises the districts of Nadia and Murshidabad (except Kandi sub-division).

Question 30.
What is ‘Diyara’?
Answer:
‘Diyara’ is the region of new silt deposition in the district of Malda. This is a part of the Ganga delta. It lies in the southern part of the river Kalindi in Malda.

Question 31.
Name some glaciers of the Karakoram range.
Answer:
Some important glaciers of the Karakoram range are – Siachen, Baltora, Rimo etc. Siachen is the longest glacier of India. (76 km.)

Question 32.
How far does the Himalayan range stretch from west to east ?
Answer:
The Himalayan range stretches from Nanga Parvat in Kashmir in the west to Namcha Barwa in Arunachal Pradesh in the east.

Question 33.
Where is the Ladakh range situated ?
Answer:
The Ladakh range is situated between the Indus and Sayak rivers in Kashmir. It is 350 km long, 150 km wide and about 5,300 m in height in average.

Question 34.
Name two famous valleys in Himachal Pradesh.
Answer:
Two famous valleys in Himachal Pradesh are – Kullu Valley and Kangra Valley. Question 35. Which part of the Himalayan range is known as the Eastem Himalayas?
Answer: The stretch of the Himalayan mountains lying between the Singalila range in Nepal to the Namcha Barwa peak in Arunachal Pradesh is known as the Eastern Himalayas.

Question 36.
Which part of the Himalayan range is known as the Western Himalayas?
Answer:
The stretch of the Himalayan mountains lying between the Nanga Parvat in Kashmir in the west to the river Kali in Nepal in the east, is known as the Western Himalayas.

Question 37.
What is the Tethys Himalaya ?
Answer:
The northernmost range of the Himalaya is known as the Tethys Himalaya.

Question 38.
What is the Himadri Himalaya?
Answer:
The second range of the Himalaya from north to south is known as the Himadri Himalaya. It is the highest of all the ranges and houses the series of the tallest peaks of the world. It lies between the Tethys Himalaya in the north and the Himachal Himalaya in the south.

Question 39.
Name some famous valleys lying in the Siwalik region.
Answer: Some famous valleys lying in the Siwalik region are – Dehradun, Chaukhamba, Patali etc. These narrow valleys are also known as ‘doons’.

Question 40.
Name the ranges that lie north of the Kashmir valley.
Answer:
The Himadri and the Zanskar range lies to the north of the Kashmir Valley.

Question 41.
Name some famous peaks of the Himadri range.
Answer:
Some famous peaks of the Himadri Himalaya are – Mt. Everest, Kanchenjunga, Dhabalgiri, Nanda Devi, Makalu etc.

Question 42.
Name the mountain passes that connect Sikkim and Tibet.
Answer:
The mountain passes that connect Sikkim and Tibet are Nathu-La and JelepLa. [La means pass]

Question 43.
Which pass connects Leh with Srinagar?
Answer:
Leh is connected to Srinagar by the zojila pass.

Question 44.
Which is the highest mountain pass of the world ?
Answer:
The highest mountain pass of the world is Karakoram pass. It helps to connect Kashmir with China.

Question 45.
Name some famous peaks of the Karakoram range.
Answer:
Some famous peaks of the Karakoram range are – Godwin Austin or K₂(8,611 m), Hidden Peak (8,068 m), Broad Peak (8,047 m), Gaserbrum peak (8,035 m) etc.

Question 46.
Name some famous lakes in the Kumaon Himalaya.
Answer:
Some famous lakes in the Kumaon Himalaya are – Bhimtal, Sattal, Nainital etc.

Question 47.
Where is the Kangra Valley situated ?
Answer:
The Kangra Valley is situated between the Siwalik and Dhawladhar ranges.

Question 48.
Classify the northern plain of India.
Answer:
The northern plain can be classified as – (i) Rajasthan plains or Marusthali (ii) Punjab plains (iii) Ganga plains (iv) Brahmaputra plains.

Question 49.
What do you mean by the ‘Purvachal’?
Answer:
The Himalayan range in the eastern part gets lowered and takes a hair-pin bend and spread southwand. They divide into several lower ranges that spread through Arunachal Pradesh, Assam, Nagaland, Manipur, Mizoram and Tripura. This hilly region in North-Eastern India is known as the ‘Purvachal’.

Question 50.
What is ‘Rohi’ of the Rajasthan plains?
Answer:
In the Rajasthan plains, small and narrow flood plains created by small streams flowing down the western slopes of the Aravalli range, are called ‘Rohi’.

Question 51.
What is a ‘Doab’?
Answer:
The small narrow stretch of land washed by rivers on both sides is called a ‘Doab’. It is a highly fertile long stretch of land created by silt deposition by the rivers on either side.

Question 52.
What is Bhabar?
Answer:
Bhabar is the region formed at the foothills of the Siwalik range stretching from river Indus in the west to river Teesta in the east. The region is composed of pebbles, rock fragments, coarse sand, mud particles etc. brought down by the numerous rivers.

Question 53.
Name two block mountains of India.
Answer:
i. Satpura range
ii. Vindhya range.

Question 54.
Name two residual mountains of India.
Answer:
i. Aravalli range
ii. The Eastern ghats.

Question 55.
Name two gaps present in the Western ghats.
Answer:
i. Thal ghat near Nasik
ii. Bhor ghat near Pune.

Question 56.
Why is the western coast of India more broken compared to the eastern coast?
Answer:
The western coastal plains have been formed by continuous submergence and emergence of the Western Ghats due to numerous earth movements. Hence, they are broken. But the eastern coast has been formed by deposition of silt brought down by several rivers. Thus, they are not so broken or interrupted.

Answer in brief : 3 Marks

Question 1.
Write a short note on the Karakoram range.
Answer:
The Karakoram range is bounded on the north-east by the Tibetan plateau, on the north by the Pamir plateau and on the south by rivers Indus, Gilgit and Shyok. These are very high mountains. Godwin Austin (8,611 m) is the highest peak of Karakoram. It is also known as the K₂ (King of Karakoram). It is India’s highest and the world’s second highest peak. Baltoro (60 km long), Siachen (90 km long, longest in India) etc. are some major glaciers of the Karakoram.

Question 2.
Describe the Eastern Himalaya.
Answer:
The Eastern Himalaya lie in north of West Bengal, Sikkim and Arunachal Pradesh in India, and in Bhutan. These are comparatively lower than the Western and Central Himalaya. Mt. Kanchenjunga is the highest peak of this region and the third highest peak of the world. An important mountain pass ‘Nathula’ lies between India and Tibet.

The north-eastem region of India, comparising of the states of Arunachal Pradesh, Assam, Manipur, Meghalaya, Mizoram, Negaland and Tripura, also form a part of the Eastern Himalayas. Low hills like Garo, Khasi, Lushai, Patkai, Jayantia, etc. make 2 / 3 of the hilly region, intersected by valleys and plains. Important rivers like Brahmaputra and Barak flow through this region.

Question 3.
Describe the Siwalik range.
Answer:
The southernmost range of the Himalayas, stretching from west to east are known as the Siwalik. They form the foothills of the Himalayan range. The mountains are 600-1500 m high, with a width ranging from 15-50 km. They form a chain of low lying hills, that do not form a continuous chain. They enclose broad longitudinal valleys between the mountains, which are known as Doabs. The foothills of the Siwaliks are known as the Terai. The Siwalik range almost vanishes in the Eastern Himalayas due to heavy rates of erosion.

Question 4.
Describe the Plains of Rajasthan.
Answer:
The areas of the north-west, west and south-west of the Aravalli are known as the western plains of Rajasthan. The region is marked by various types of erosional features. The plain is basically stony and slopy from the foothills of the Aravallis to the north-west. Rivers Banas, Mahi and their numerous tributaries drain the region. The deeply dissected area of chappan region in the southeastern part is locally called ‘Bagar’. Southern and south-eastern Rajasthan is mostly a plateau.

Question 5.
Describe the Western Ghats.
Answer:
The Western Ghats or the Sahyadris have an average height of 1200 m and run almost parallel to the west coast for about 1600 km. The Nilgiri, Cardamom and Annamalai hills are parts of the Western Ghats. Anaimudi (2,695 m) of Annamalai is the highest peak of this region. The Dodabeta (2,637 m) is the highest peak of Niligiri hills. Important passes in the Western Ghats are Thal Ghat, Pal Ghat and Bhor Ghat. The Jog falls (250 m) is the highest waterfalls of India, located in the Sahyadri, on the river Sharavati.

Question 6.
Write a short note on the Kathiawar Peninsula.
Answer:
The Kathiawar peninsula lie in the western part of Gujarat surrounded by the Arabian sea on three sides. Traditionally it is known as Saurashtra. Its central part is an elevated.highland with hills. The Girnar and Gir hills are most prominent. Gorakhnath (1,117 m) is the highest peak of Girnar hills.

Question 7.
Write a short note on the Eastern Coastal Plains.
Answer:
The eastern coastal plains extend from the mouth of river Hugli to Kanya Kumari. It has an average width of 120 km. These are known as the Uttar Sarkars north of the delta of the Godavari river, and the Coromondal coast to the south of the delta.

Question 8.
Describe the Himachal Himalaya.
Answer:
The Himachal Himalaya lie north of the Siwalik range and south of the Himadri Himalaya. It is about 60-80 km wide and cover an area of 5,600 sq. km. The average height of the peaks is 3,500-4,500 m. The main ranges of this region are – Pir Panjal, Dhawladhar, Nagtibba, Mussurie, Mohabharat, Darjeeling etc. There are many famous valleys in this region, eg- Kashmir Valley, Kullu Valley, Kangra Valley etc. The main mountain passes present here are – Rotang, Nathula, Pir Panjal, Bidil, Banihal etc.

Question 9.
Describe the Himadri Himalaya.
Answer:
The Himadri Himalaya is the highest of the Himalayan mountain system, lying south of the Tethys Himalaya. Average height of the peaks is above 6,100 m. There are 9 peaks in this region whose height exceeds 8,000 m. The most important peaks of this region are – Mt. Everest (8848 m), Kanchenjunga (8,598 m), Makalu (8,481 m), Dhabalgiri (8,172 m), Nanga Parvat (8,126 m), Nanda Devi (7,817 m), Kamet (7,756 m), Badrinath (7,138 m), Trishul (7,120 m), Gauri Shankar (7,032 m) etc.
The region is mostly covered with permanent snow throughout the year.

Question 10.
Describe the Tethys Himalaya.
Answer:
The Tethys Himalaya is the northernmost part of the Himalayan mountain range. It mostly lie in Tibet, hence, it is also called the Tibet Himalaya. The Tethys Himalaya stretches over Jammu and Kashmir and Himachal Pradesh in India. It was created about 12-7 crore years ago due to severe earth movements. Average height of this region is 3,500 m. The main mountain ranges of this region are the Ladakh range and the Karakoram range. The famous peaks of this region are – Godwin Austin or K₂, Gaserbrum I and II, Broad Peak, Hidden Peak etc. K₂ is the highest mountain peak of India.

Question 11.
Name the important mountain passes of the Himalayas and give their locations.
Answer:

Mountain Passes	Location and connecting places
1. Jawahar or Banihal	Connects Jammu and Kashmir
2. Zoji la and Burji la	Connects Leh and Srinagar
3. Masar	Connects Leh and Tibet
4. Khardung La	Between Indus valley and Nabra valley
5. Lipu pass, Mana pass and Niti pass	Connects different parts of Uttarakhand and Tibet.
6. Rotang, Barlacha and Shipki la pass	Between Kullu and Lahut Spiti valleys
7. Nathu la, Jelep la	Connects Sikkim and Tibet
8. Ann and Tungu	Situated in Assam
9. Dom la, Thag La, Kay La, Tullang La	Connects different parts of Arunachal Pradesh with Tibet.

Question 12.
What is a ‘doon’?
Answer:
The valleys lying in the Siwalik range are called ‘doons’. The Siwalik range has been formed much later than the Himadri and Himachal Himalaya. During the formation of the Siwalik, the rivers that were flowing from the higher Himalayan ranges got interrupted and blocked, thus forming lakes and depositing pebbles, sand, silt etc. Later, the rivers eroded and made their ways through the Siwalik range as well. Thus, the waters of the lakes were removed.The depositions left back formed the ‘doons’.

Question 13.
Name some springs of the Himalayan mountains.
Answer:
(i) Hot springs : (a) Bhernag, Anantnag in Kashmir, (b) Gauri Kund in Kumaon range, (c) Tatapani in Simla etc.
(ii) Cold springs : (a) Sahastradhara in Dehradun, (b) Kempty falls in Mussoorie.

Question 14.
Name some important lakes of the Himalayan range.
Answer:
The important lakes of the Himalayan region are:

1. Dal and Wular in Kashmir
2. Nainital, Sattal, Bhimtal, Naukuchiatal etc. in Kumaon.
3. Vasuki tal, Chorabar tal near Kedarnath.
4. Roopkund, Nag kund, Devi kund near Nanda Ghunti peak.
5. Hem kund in Bhunjar valley
6. Suram kund near Nanda Devi
7. Pangon lake near China border (world’s highest salt water lake)

Question 15.
Name some important glaciers of the Himalayan range.
Answer:

1. Siachen -76 km (Spread over area)
2. Baltaro -60 km             “
3. Biyafo – 60 km              “
4. Hispar – 62 km              “
5. Gangotri -39 km           “
6. Zemu -26 km                “
7. Milam -39 km               “

Answer in details : 5 Marks

Question 1.
Describe the physiographic divisions of the Himalaya.
Answer:
The Himalaya is not a single continuous chain of mountains, but a series of parallel ranges. This can be divided into three main ranges that run parallel to each other. These are :

(a) The Greater Himalaya or the Himadri : It is the highest part of the Himalaya. The average elevation of the Himadri is 6000 m, and is permanently covered with snow. Mount Everest (8,848 m), the highest peak of the world is located here. There are some other peaks such as Kanchenjunga (8,598 m, world’s 3rd highest), Dhaulagiri ( 8,172 m), Nanga Parbat (8,126 m), Annapurna (8,076 m), Nandadevi (7,817 m) etc. Glaciers like Gangotri, yamunotri etc. originate in the Himadri.

(b) The Lesser Himalaya or the Himachal : It is a massive mountainous tract about 75 km wide and lies south of Himadri. It has an average elevation of 4,500 m. This mountain belt is highly dissected. Many of the hill stations, such as Simla, Nainital, Mussoorie, Darjeeling etc. are situated in this belt.

(c) The Outer Himalaya or Siwalik : It is the southernmost range of the Himalaya. It forms the foothills of the Himalayan range. It is 600-1500 m high with a width ranging from 15-50 km. It is a chain of low-lying hills. It is not a continuous range. There are broad longitudinal valleys in the siwalik, known as Doons. Foothills of Siwalik are known as Terai.

Question 2.
What are the importances of the Himalaya to India ?
ans.
The Himalayas have a lot of importance in India :

1. Climatic influence : The Himalaya prevents the cold winds from central Asia from entering India. It also prevents the moisture-laden monsoon winds from escaping from the land.
2. Rainfall: The Himalaya stope the monsoon winds from escaping the Indian landmass. The monsoon winds hit against the great mountain wall and cause orographic rainfall in the Indian plains.
3. Birth place of rivers : The orographic rainfall and snow-melt water give rise to numerous rivers.
4. Natural barrier : The Himalayas form a natural boundary on the north and protect the country from foreign invasions.
5. Fertile soil : The eroded materials from the mountains are deposited in the plains to make them fertile.
6. Source of irrigation, navigation and hydel power: The Himalayan rivers provide water for irrigation, navigation and hydel power generation.
7. Forest products : The Himalayan forests provide plenty of forest resources.
8. Flora and Fauna : The Himalayan forests are rich in numerous species of animals and natural vegetation.
9. Others : The Himalaya is an abode of tourists, storehouse of minerals, source of various fruits etc.

Question 3.
What is the importance of the peninsular plateau of India.
Answer:
The importance of the peninsular plateau of India are :

1. The Deccan plateau is mostly comprised black cotton soil, or regur. This region is best for the cultivation of cotton in India.
2. About 60% of the peninsular plateau is used for cultivation of jowar, bajra, wheat and rice.
3. The region is rich in mineral resources like coal, iron ore, manganese, limestone, chromite etc. which serve as raw materials for various industries.
4. Industries like cotton textile, sugar, edible oil, paper, engineering have prospered in this region.

Question 4.
Discuss the importance of the physiographic divisions of India.
Answer:
The importance or significance of the physiographic divisions of India are:

1. The variety of landforms and physical features make India a unique country.
2. The presence of mountains, plateaus, plains, deserts etc. significantly control the climate, social life and economic activities of people.
3. People on the mountains lead a tough life. Their economy mostly stands on tourism, fruit orchards, timber collection etc.
4. The people on plain lands practice agriculture, industrial activities etc.
5. Presence of mountains help in occurrence of numerous rivers that bring down a significant amount of silt.
6. The desert in the west gets heated excessively during summer, creating a low pressure cell, that attracts the monsoon winds.
7. The plateau region is a store-house of minerals with mine related occupations.

Question 5.
Discuss the importance of the Himalaya in controlling climate of India.
Answer:
The Himalaya stretches from west to east for about 2,500 km along the northern boundary of India. It has a very big influence on the climate of the country.

1. The existence of the Himalayas prevent the severely cold polar winds coming from Siberia to enter the mainland. Thus, the country is saved from the chilling colds.
2. The Himalayan mountains indirectly influence the onset of the monsoon winds.
3. The South-West monsoons cause orographic rainfall after colliding with the southern slopes of the Himalayan mountains.
4. Although located in the sub-tropical region, the altitude of the Himalayan range and its adjacent areas help to keep the climate cool and of temperate type.
5. The seasons of the country are mostly controlled by the Himalayas directly or indirectly.

Multiple Choice Questions (MCQ) : 1 Mark

Question 1.
Which of the following regions has the oldest rocks?
(A) Himalaya
(B) Aravalli
(C) Indo-Gangetic Plain
(D) Siwalik
Answer:
(B) Aravalli

Question 2.
Jojila pass is in :
(A) Kashmir
(B) Himachal Pradesh
(C) Uttar Pradesh
(D) None of these
Answer:
(A) Kashmir

Question 3.
The Himalaya in approximately – kilometre long.
(A) 2000
(B) 2500
(C) 3000
(D) 1500
Answer:
(B) 2500

Question 4.
The Himalaya is approximately broad _________ kilometer.
(A) 150 to 400
(B) 200 to 400
(C) 150 to 300
(D) 250 to 500
Answer:
(A) 150 to 400

Question 5.
The highest peak, Mount Everest is :
(A) 290.28 feet
(B) 285.28 feet
(C) 273.28 feet
(D) 269.84 feet
Answer:
(A) 290.28 feet

Question 6.
The Himalaya consists of _________ main parallel ranges from north to south
(A) two
(B) three
(C) four
(D) five
Answer:
(B) three

Question 7.
Sajhyadri ranges refer to :
(A) Siwalik
(B) Eastern Ghats
(C) Western Ghats
(D) Satpura Range
Answer:
(C) Western Ghats

Question 8.
Banihal pass is in :
(A) Punjab Himalaya
(B) Kumaun Himalaya
(C) Kashmir Himalaya
(D) Assam Himalaya
Answer:
(C) Kashmir Himalaya

Question 9.
Lahul and Spiti are located in :
(A) Kashmir Himalaya
(B) The Naga Hills
(C) The Assam Himalaya
(D) The Punjab Himalaya
Answer:
(D) The Punjab Himalaya

Question 10.
Nanda Devi lies in :
(A) Kumaun Himalaya
(B) Kashmir Himalaya
(C) Naga Hills
(D) Himachal Himalaya
Answer:
(A) Kumaun Himalaya

Question 11.
The plains of North India have the length of :
(A) 2500 km.
(B) 2300 km.
(C) 2400 km.
(D) 2250 km.
Answer:
(D) 2250 km.

Question 12.
Pir Panjal range is in :
(A) The Greater Himalaya
(B) The Middle Himalaya
(C) Siwalik
(D) Sikkim Himalaya
Answer:
(A) The Greater Himalaya

Question 13.
The average height of Siwalik is :
(A) 1500 to 2000 metre
(B) 1000 to 1500 metre
(C) 700 to 1000 metre
(D) None of these
Answer:
(A) 1500 to 2000 metre

Question 14.
Kashmir Himalaya is famous for its :
(A) Scenic beauty
(B) Dal Lake
(C) Glaciers
(D) Poverty
Answer:
(C) Glaciers

Question 15.
The Karewas of Kashmir refers to :
(A) The alluvial fans
(B) The ravines caused by gully erosion
(C) Glacial deposits
(D) Broad river terraces
Answer:
(C) Glacial deposits

Question 16.
Extensive and thick lava sheets occur in :
(A) Meghalaya
(B) Chotanagpur Plateau
(C) Western Deccan Plateau
(D) Nilgiri Hill
Answer:
(C) Western Deccan Plateau

Question 17.
Natravathi rises in the mountain range of :
(A) Western Ghat
(B) Satpura Range
(C) Eastern Ghat
(D) Aravalli Range
Answer:
(A) Western Ghat

Question 18.
Western Coastal plains of India are :
(A) Flat
(B) Round
(C) Level
(D) None of these
Answer:
(A) Flat

Question 19.
How much percentage land area of India is covered by mountains?
(A) 10.7
(B) 12.7
(C) 9.7
(D) 11.7
Answer:
(A) 10.7

Question 20.
The area of Ganga plain is :
(A) 3,57,000 sq. km.
(B) 3,20,000 sq.km.
(C) 3,50,000 sq.km.
(D) 3,40,000 sq.km.
Answer:
(A) 3,57,000 sq. km.

Question 21.
The Great plain has been subjected to …. throughout its period of existence.
(A) the denudation processes
(B) the degradational processes
(C) the aggradational processes
(D) the weathering processes
Answer:
(C) the aggradational processes

Question 22.
The Garo, Khasi and Jaintia hills were formed in the same age as the :
(A) Himalaya
(B) Siwalik range
(C) Malwa plateau
(D) Himachal range
Answer:
(C) Malwa plateau

Question 23.
The vigorous glacial action of the Himalayan rivers in the past is proved by :
(A) the awe-inspiring gorges
(B) the sedimentary beds of the Kashmir valley
(C) the hanging valleys at lower altitudes
(D) the frequent shifts in the courses of the rivers
Answer:
(C) the hanging valleys at lower altitudes

Question 24.
Palghat is a mountain pass of :
(A) Eastern Ghat
(B) Satpura
(C) Western Ghat
(D) Maikal Range
Answer:
(C) Western Ghat

Question 25.
The name of the desert of Rajasthan is :
(A) Bagar
(B) Rohi
(C) Hamada
(D) Marusthali
Answer:
(D) Marusthali

Question 26.
What is the most important geographic use of the Himalayas to India?
(A) Prevention of invasions
(B) Valuable source of timber
(C) They prevent the monsoons from crossing to the north and also serve as a reservoir of water from which our perennial rivers flow
(D) They protect India from the icy cold north winds
Answer:
(C) They prevent the monsoons from crossing to the north and also serve as a reservoir of water from which our perennial rivers flow

Question 27.
Which of the following mountains are the oldest according to geological history?
(A) Nilgiri
(B) Satpura Range
(C) Vindhya
(D) Aravalli
Answer:
(D) Aravalli

Question 28.
Where mainly in India would you find denuded rocks ?
(A) Himalayan region
(B) Peninsular Plateau
(C) Valleys
(D) Everywhere
Answer:
(B) Peninsular Plateau

Question 29.
The average height of the Himalaya is :
(A) 5850 metre
(B) 9050 metre
(C) 4800 metre
(D) 5000 metre
Answer:
(A) 5850 metre

Question 30.
India’s coastline is long to the extent of :
(A) 1400 mile
(B) 1000 mile
(C) 3500 mile
(D) 5100 mile
Answer:
(C) 3500 mile

Question 31.
The west coast of India is :
(A) Levelled
(B) Low lying
(C) Very well indented
(D) None of these
Answer:
(C) Very well indented

Question 32.
The Lakshadwees islands are located in :
(A) Bay of Bengal
(B) Arabian Sea
(C) Indian Ocean
(D) Persian Gulf
Answer:
(B) Arabian Sea

Question 33.
Purvanchal refers to the :
(A) Mountain ranges on the eastern borders or India
(B) Eastern Ghats
(C) Chotanagpur Plateau
(D) Assam Himalayas
Answer:
(A) Mountain ranges on the eastern borders or India

Question 34.
The Himalayan ranges consist of
(A) A single range with peaks exceeding 8000 metres
(B) Three parallel ranges with intervening longitudinal valleys
(C) Two parallel ranges with a plateau in between
(D) Four parallel ranges
Answer:
(B) Three parallel ranges with intervening longitudinal valleys

Question 35.
Highest peak of Deccan plateau of Southern India is :
(A) Dodabeta
(B) Patkoi
(C) Anaimudi
(D) Gurushikhar
Answer:
(C) Anaimudi

Question 36.
Name the coast where the lagoons are locally known as Kayal :
(A) Malabar
(B) Konkan
(C) Coromandel
(D) Karnataka
Answer:
(A) Malabar

Question 37.
Highest peak of Aravalli Hills :
(A) Dodabeta
(B) Gurushikhar
(C) Dhupgarh
(D) Amar Kantak
Answer:
(B) Gurushikhar

Question 38.
Highest peak of Satpura hills :
(A) Dhupgarh
(B) Anaimudi
(C) Sadal Peak
(D) Nanga Pahar
Answer:
(A) Dhupgarh

Question 39.
The main difference between the Eastern Ghats and the Western Ghats is in the matter of :
(A) continuity
(B) proximity to coast
(C) ending in Nilgiri
(D)height
Answer:
(A) continuity

Question 40.
The region on the southern side of the Siwalik is called the :
(A) Dunes
(B) Bhabhar
(C) Terai
(D) Khadar
Answer:
(B) Bhabhar

Question 41.
The Nilgiri is part of the :
(A) Eastern Ghats
(B) Western Ghats
(C) Vindhyachal
(D) Tamil Nadu Hills
Answer:
(B) Western Ghats

Question 42.
Which of the following is characterised by excessive dampness with a thick growth forest and a variety of wildlife ?
(A) Bhabhar
(B) Bhangar
(C) Terai
(D) Khadar
Answer:
(C) Terai

Question 43.
Match the following

Answer:

Question 44.
Lakshadweep island is of :
(A) Coral origin
(B) Volcanic origin
(C) Tectonic origin
(D) Alluvial origin
Answer:
(A) Coral origin

Question 45.
India has total land frontier of :
(A) 10000 mile
(B) 12000 mile
(C) 9425 mile
(D) 7000 mile
Answer:
(C) 9425 mile

Question 46.
The average elevation of Vindhya mountain is :
(A) 500 metre
(B) 200 metre
(C) 400 metre
(D) 300 metre
Answer:
(D) 300 metre

Question 47.
The Ganga-Indus Plain widens :
(A) from east to west
(B) from west to east
(C) at the middle
(D) nowhere
Answer:
(A) from east to west

Question 48.
The Peninsular Plateau of India extends up to :
(A) Mizo hills
(B) Himachal Himalayas
(C) Assam valley
(D) Meghalaya hills
Answer:
(D) Meghalaya hills

Question 49.
What is the most important characteristic of the islands (Indian) located in the Arabian Sea?
(A) They are all very small in size
(B) They are all of coral origin
(C) They have a very dry climate
(D) They are extended parts of the mainland
Answer:
(B) They are all of coral origin

Question 50.
What do the basalt layers of the Dcccan indicate?
(A) The influence of weathering
(B) The immense erosional activity of the rivers
(C) Huge volcanic eruptions in the distant past
(D) All the above
Answer:
(C) Huge volcanic eruptions in the distant past

Question 51.
Highest peak of Anaimalai range :
(A) Anaimudi
(B) Amarkantak
(C) Kalsubai
(D) Mahendragiri
Answer:
(A) Anaimudi

Question 52.
The coast of Tamil Nadu is known as :
(A) Malabar
(B) Konkan
(C) Andhra coast
(D) Coromandel
Answer:
(D) Coromandel

Question 53.
The coast of Kerala is known as :
(A) Uttar Sarkar
(B) Coromondel
(C) Malabar
(D) Konkan coast
Answer:
(C) Malabar

Question 54.
Highest plateau of India is :
(A) Deccan Plateau
(B) Ladakh
(C) Meghalaya
(D) Malab Plateau
Answer:
(B) Ladakh

Question 55.
Which of the following ranges separates the Kashmir valley from the Indus valley?
(A) Siwalik range
(B) Pir Panjal range
(C) Dhauladhar range
(D) Great Himalayan range
Answer:
(D) Great Himalayan range

Question 56.
Which of the following ranges act as a natural barries between India and Tibet?
(A) Jelep La
(B) Kalimpong
(C) Lipu Lekh
(D) Himalayas
Answer:
(D) Himalayas

Question 57.
______ is known as the Queen of the Himalayas.
(A) Dhawlagiri
(B) Kanchanjunga
(C) Nandadevi
(D) K₂
Answer:
(B) Kanchanjunga

Question 58.
The Garo, Khasi and Jayantia hills were formed in the same age as the :
(A) Himalayas
(B) Siwaliks
(C) Malwa Plateau
(D) Himachal
Answer:
(C) Malwa Plateau

Question 59.
________ is considered as the remnant of the Gondwanaland.
(A) The gangetic plain
(B) The Himalayas
(C) The Deccan plateau
(D) The Punjab Plains
Answer:
(C) The Deccan plateau

Question 60.
The largest plateau of india is :
(A) Betwa plateau
(B) Deccan plateau
(C) Malwa plateau
(D) Chotanagpur plateau
Answer:
(B) Deccan plateau

Question 61.
Mt. Abu, a small hilly block is separated from the Aravalli range by :
(A) Malwa plateau
(B) Guru-Sikhar valley
(C) Narmada valley
(D) Banas valley
Answer:
(D) Banas valley

Question 62.
Bhabar and Terai belts are wellformed in :
(A) Uttar Pradesh
(B) Bihar
(C) West Bengal
(D) Assam
Answer:
(A) Uttar Pradesh

Fill in the blanks : 1 Mark

1. Himalayas owe its origin in the _______ Epoch.
2. According to geological history, the oldest mountain is Aravalli, and the youngest is _______.
3. _______ is the highest peak of the Naga Range.
4. The length of the Himalayas between Indus gorge and Brahmaputra gorge is _______ km.
5. Nokrek is the highest peak of the _______ hills.
6. The Malwa plateau is a _______ plateau.
7. The North-Indian plains extend for _______ km between the mouth of the Ganga and the Indus.
8. The total length of India’s coastline is about _______ km.
9. The _______ range forms the water divide between Narmada and Tapti rivers.
10. The Himalayas run in the East-West direction along the entire northern boundary of India for _______ km.
11. The lesser or middle Himalayas have an average elevation of about _______ m.
12. Aravalli hills are located in the _______ of the Malwa plateau.
Answer:
1. Oligocene
2. Himalayas
3. Saramati
4. 2400 km
5. Garo
6. Piedmont
7. 3200
8. 7500
9. Satpura
10. 2400
11. 3500-5000 m
12. North-West

State True or False : 1 Mark

1. Malabar coast is a part of Eastern coast of India. [ ]
2. Dehradun valley, Udhampur valley, chaukhamba valley, etc. are located in the Siwaliks. [ ]
3. Nagtibba is the most important range of the lesser Himalayas. [ ]
4. The Siachen glacier is located in Nubra valley. [ ]
5. Zanskar and PIr Panjal ranges are located in Himachal Pradesh [ ]
6. Aravalli range is an example of block mountains. [ ]
7. Andhra Pradesh has the largest coast line in India [ ]
Answer:
1. True
2. True
3. False
4. True
5. False
6. False
7. True

Match the following : 1 Mark

List I	List II
A. Zojila pass	i. Sikkim
B. Bara Lacha La pass	ii. Uttar Pradesh
C. Niti pass	iii. Himachal Pradesh
D. Jelep la pass	iv. Kashmir

Answer:

List I	List II
A. Zojila pass	iv. Kashmir
B. Bara Lacha La pass	iii. Himachal Pradesh
C. Niti pass	i. Sikkim
D. Jelep la pass	ii. Uttar Pradesh

Answer in few words : 1 Mark

Question 1.
Which is the highest peak of India ?
Answer:
Godwin Austin or K₂(8,611 m)

Question 2.
Where is the highest peak of India located ?
Answer:
In the Karakoram range.

Question 3.
Where does the largest glacier of India lie?
Answer:
Largest glacier of India, Siachen (90 m) lies in the Karakoram range.

Question 4.
What is the other name of the greater Himalaya ?
Answer:
The Himadri.

Question 5.
What is the other name of the outer Himalayas?
Answer:
The Siwalik.

Question 6.
Name the regional divisions of the Himalayas.
Answer:

• Western Himalaya
• Central Himalaya
• Eastern Himalaya.

Question 7.
Which rivers drain the plains of Rajasthan ?
Answer:
River Banas, Mahi and their numerous tributaries.

Question 8.
Name the highest peak of the Satpura range.
Answer:
Dhupgarh (1,350 m)

Question 9.
Name the another identity of the Western Ghats.
Answer:
Sahyadris.

Question 10.
Which is the highest peak of the Deccan plateau ?
Answer:
Anaimudi (2,695m) of Annamalai hills.

Question 11.
Which is the highest peak of the Nilgiri hills ?
Answer:
Dodabeta (2,637 m)

Question 12.
Name the highest waterfalls of India.
Answer:
The Jog Falls (250 m) on the river Sharavathi.

Question 13.
Which is the highest peak of the Eastern Ghats ?
Answer:
Mahendragiri (1,501 m)

Question 14.
Name the oldest mountain range of India.
Answer:
Aravalli range.

Question 15.
Which state of India is known as the ‘Land of five mountains’?
Answer:
Tripura.

Question 16.
Name the highest peak of the Aravalli range.
Answer:
Gurushikhar.

Question 17.
Name the lava plateau of India.
Answer:
The Deccan plateau, the Malwa plateau.

Question 18.
Name a dead volcano present in India.
Answer:
Narkondam of the Andaman and Nicobar islands.

Question 19.
Which is the easternmost mountain range of India ?
Answer:
Namchabarwa.

Question 20.
Which pass connects Kashmir Valley to Leh ?
Answer:
The Zojila Pass.

Detailed explanations in West Bengal Board Class 10 Geography Book Solutions Chapter 5.1 Location and Administrative Divisions of India offer valuable context and analysis.

WBBSE Class 10 Geography Chapter 5.1 Question Answer – Location and Administrative Divisions of India

Answer in brief : 2 Marks

Question 1.
State the boundaries of India.
Answer:
The boundaries of India are:

1. North → China, Nepal and Bhutan.
2. North-West → Pakistan and Afghanistan.
3. West → Pakistan and Bay of Bengal.
4. South → Sri Lanka and Indian Ocean.
5. East → Bangladesh, Myanmar and Bay of Bengal.

Question 2.
Why is India called a Peninsula ?
Answer:
India is bounded by three water bodies on three sides (Arabian sea in the West Indian Ocean in the South, Bay of Bengal in the East) and attached to land only on the north. Thus it is called a Peninsula.

Question 3.
What is the name of the boundary between India and China and India and Pakistan?
Answer:
Boundary between India and China Macmohan Line. Boundary between India and Pakistan Radcliffe line.

Question 4.
What is the LOC?
Answer:
LOC or Line of Control is the boundary between the part of Kashmir under India and the part that belongs to Pakistan.

Question 5.
Mention the latitudinal and longitudinal extent of India.
Answer:
The main landmass of India lies between the latitudes 8° 04′ 24″ N to 37° 06′ N, and longitudes 68° 07′ 53″ E to 97° 24′ 47″ E.

Question 6.
What were the criteria considered for the basis of division of states after independence?
Answer:
The basis of division of states of India after independence are – Language, Administrative advantage and skill, Culture, Physical and Geographical similarities, and Economic stability.

Question 7.
What is the position of India in Asia and the World with respect to area?
Answer:
India ranks 7^th in the world (after Russia, Canada, China, USA, Brazil and Australia) and 2^nd in Asia (after China) with respect to area.

Question 8.
What is the length of the coastline of India ?
Answer:
The length of the coastline of India including the mainland as well as the Lakshadweep and Andaman and Nicobar Islands is 7,517 km.

Question 9.
What is Indira Point ?
Answer:
Indira Point is the southernmost point of India. It is the southernmost point of the great Nicobar Island. Previously it was known as the Pymalian point.

Question 10.
Name 4 states of India lying in the north east.
Answer:
Assam, Meghalaya, Manipur, Nagaland.

Question 11.
Name 4 Union Territories of India.
Answer:
Delhi, Pondicherry, Chandigarh, Andaman and Nicobar islands.

Question 12.
Name 4 states along the coast of the Bay of Bengal.
Answer:
Tamil Nadu, Andhra Pradesh (now Seemandhra), Odisha, West Bengal.

Question 13.
Name 4 states along the coast of the Arabian Sea.
Answer:
Kerala, Karnataka, Goa, Maharashtra and Gujarat.

Question 14.
Which islands are separated by the 10° Channel ?
Answer:
The 10° Channel separates the Andaman islands and Nicobar islands.

Question 15.
Which islands are separated by the 9° Channel ?
Answer:
Lakshadweep islands and Minicoy islands.

Question 16.
Which islands are separated by the 8° Channel ?
Answer:
Minicoy islands and Maidives islands.

Question 17.
What is the Durand line?
Answer:
Durand line is the boundary between India and Afghanistan. It was named in 1896.

Question 18.
How has India been designated in the constitution since 26th January 1950 ?
Answer:
Since 26 January 1950, India has been designated as a Sovereign, Socialist, Secular, Democratic, Republic country in the Constitution.

Question 19.
What is the East-West and North-South extent of India ?
Answer:
i. East-West extent of India is 2,933 km.
ii. North-South extent of India is 3,214 km.

Question 20.
How many states and Union Territories are presently there in India ?
Answer:
Presently there are 29 states and 7 Union Territories in India.

Question 21.
Name the smallest and largest states of India.
Answer:
The smallest state of India is Goa and the largest state is Rajasthan.

Question 22.
Name the smallest and largest Union Territories of India.
Answer:
The smallest Union Territory of India is Lakshadweep and the largest one is Andaman and Nicobar islands.

Question 23.
Which is the southernmost point of the mainland of India ?
Answer:
The southernmost point of the mainland of India is Kanyakumari in Tamil Nadu.

Question 24.
Name the smallest and largest neighbouring countries of India.
Answer:
The smallest neighbouring country of India is Maldives and the largest neighbouring country is China.

Question 25.
Name 2 neighbouring countries of India on the western border.
Answer:
Two neighbouring countries of India on the western border are Pakistan and Afghanistan.

Question 26.
Name 2 northernmost states of India and their capitals.
Answer:
i. Jammu \ Kashmir – Srinagar.
ii. Himachal Pradesh – Shimla.

Question 27.
Name 2 westernmost states of India and their capitals.
Answer:
i. Gujarat – Gandhinagar.
ii. Rajasthan – Jaipur.

Question 28.
Name 2 southernmost states of India and their capitals.
Answer:
i. Tamil Nadu – Chennai.
ii. Kerala – Thiruvananthapuram.

Question 29.
Name 2 easternmost states of India and their capitals.
Answer:
i. Arunachal Pradesh – Itanagar.
ii. Nagaland – Kohima.

Question 30.
Where is the Price channel located ?
Answer:
The Price channel lies between the Mini Nicobar and Great Nicobar Islands.

Answer in brief : 3 Marks

Question 1.
Mention the location and latitudinal extent and longitudinal extent of India.
Answer:
India is located in southern Asia between the latitudes -8° 04′ 24” N to 37° 06′ N and longitudes -68° 07′ 53” E to 97° 24′ 47” E. Total area is about 32 lakh 87 thousand 263 sq. km. It is bounded by the Himalayas, China, Nepal and Bhutan on the north. The North-West is bounded by Pakistan and Afghanistan. The West is bounded by Pakistan and the Arabian sea. The east is bounded by Myanmar, Bangladesh and the Bay of Bengal. The south is bounded by the Indian Ocean and Srilanka.

Question 2.
How does the peninsular location of India influence the land and life of the people?
Answer:

The advantages of the peninsular location of India are :

1. India can conduct international trade through waterways very easily due to presence of oceans and seas on three sides.
2. Nearness to sea helps in development of navigation and fishing activities.
3. Presence of the vast water bodies influences the weather and climate of the country.
4. Presence of vast water bodies give natural protection from invasions and attacks by enemies.
5. Water bodies help to maintain cordial relations with the neighbouring countries as well.

Question 3.
Discuss in brief the history of reorganisation of states of India after independence.
Answer:
The borders of the states inherited from British India were not suitable for easy administration. Hence, after independence, the need for reorganisation of states of India was felt. Several controversies arose, regarding what should be the basis of reorganisation of states. Hence, the government of India constituted the State Reorganisation commission (SRC) to undertake and resolve the issue, which passed the State Reorganisation Act in 1956. By the Act, the states were reorganised on the basis of – language, administrative skill and advantage, Culture, physical and cultural similarities and economic stability.

Question 4.
Name the various neighbouring countries of India.
Answer:
The neighbouring countries of India are:

1. Northern neighbours : China (largest neighbouring country), Nepal, Bhutan (Smallest neighbouring country touching the mainland).
2. North-Western neighbours : Afghanistan.
3. Western neighbours : Pakistan (second largest neighbouring country)
4. Southern neighbours : Sri Lanka (separated from the mainland of India by the Gulf of Mannar and Palk Strait)
5. South-Western neighbours : Maldives (smallest neighbouring country away from the mainland, south of the Lakhadweep.)
6. Eastern neighbours : Myanmar (third largest neighbouring country), Bangladesh (fourth largest neighbouring country).

Question 5.
Name the States of India that were newly formed in \mathbf{2 0 0 0 .
Answer:
The states that were formed in 2000 after breaking from the former states are:

Question 6.
Name the Union Territories of India.
Answer:
The Union Territories of India are :

1. i. Andaman and Nicobar Islands (largest)
2. Daman and Diu
3. Chandigarh
4. Dadra and Nagar Haveli
5. Pondicherry
6. Lakshadweep
7. Delhi (National Capital Region)

Question 7.
What is an ‘enclave’?
Answer:
Small areas or settlements of one particular country lying within the territories of the neighbouring countries, is called ‘enclaves’. Eg – There are 162 enclaves of Bangladesh present in Indian territory and 111 enclaves of India present within the territories of Bangladesh.
According to a historic treaty signed on 31 July 2015, between India and Bangladesh, the 162 Bangladeshi enclaves lying within India have been handed over to Bangladesh government and the families residing in those enclaves (222 families) have settled in the Indian territory. 51 enclaves of India have been converted to Indian territory so far.

Answer in details : 5 Marks

Question 1.
Discuss the various basis of division of states of India after independence.
Answer:
The basis of division of states of India after independence are :
i. Language : India is a land where people speak different languages in different parts of the country. Based on this, the states were demarcated in 1956, designating the region speaking a common language as one state. Eg-the region where people mostly speak Assamese was demarcated as Assam.

ii. Administrative advantage and skill : Although language was a criterion of demarcating states, only this could not work very well. Eg-Hindi is spoken in Uttar pradesh, Bihar, Jharkhand, Madhya Pradesh and Uttaranchal. But if all these states were kept united as one single state, it would have covered a huge area, causing difficulty in administration. Also, Bengali is spoken in West Bengal and Tripura. But due to physical distance, these two states could not be put together.

iii. Culture : Even though language spoken is the same, the local cultures and rituals followed in a particular region may vary. Hence, for administrative efficiency, these regions are fragmented into different states. Eg-Bihar has been fragmented into Bihar and Jharkhand.

iv. Physical and geographical similarities : Physical and geographical conditions influence the culture and life style of people. It also plays an important role in administrative works.

v. Economic stability : Uniform economic condition helps in planning and execution of administrative and developmental works. Hence, economic condition of the region is also judged before demarcating a state.

Question 2.
State the division of states that occured in India from 1947 to 1950 , after independence.
Answer:
India achieved its freedom on 15 August 1947. On 14 and 15 August, the mainland was divided into two countries – India and Pakistan. The part of independent India was divided into 9 governor ruled states, 4 chief commissioner ruled states and more than 600 independent small national states. In 1948-49, by the efforts of Sardar Ballav Bhai Patel, the smaller national states were included within the mainland of India. In 1949, when the Constitution of India was framed and accepted on 26 January, there were 28 states and one National Territory in India.

Question 3.
Discuss the importance of the geographical location of India.
Answer:

The importance of the geographical location of India are as follows :
i. Central location : The portion of India from 10° N-23[altex]\frac{1}{2}[/latex]° N latitudes lie in the tropical region and the portion from 23 [altex]\frac{1}{2}[/latex]° N 30° N latitudes lie in the sub-tropical region.

ii. Central location within Asia : India lies in the centre of the South Asian countries. Thus, it plays an important role in trade and commerce between the SouthEastern and South-Western countries of Asia.

iii. Effects on the Indian Ocean : India being located just at the north of the Indian Ocean, influences the currents of the Indian Ocean to a large extent.

iv. Trade through waterways : India being surrounded by seas and oceans on three sides (Arabian Sea in the west, Indian Ocean in the south, Bay of Bengal in the east) enjoys a great advantage in trade by waterways with other countries.

Natural boundary : India enjoys natural boundaries on almost all sides – the Himalaya in the north, Arabian Sea and the Thar desert in the west, Indian Ocean in the south, Bay of Bengal in the east. This has provided natural security to the land and has helped to reduce expenses on millitary and security purposes.

vi. Relation with neighbouring countries : India is a very important member of the foundation called SAARC (South Asian Association of Regional Co-operation). It helps to promote and protect the interests of the neighbouring countries of Pakistan, Nepal, Bhutan, Bangladesh, Sri Lanka and Maldives.

Question 4.
Why are the countries of India and its neighbours together called ‘Indian subcontinent?
Answer:
India along with its neighbours Pakistan, Nepal, Bhutan, Bangladesh and Sri Lanka are known as the ‘Indian subcontinent’. This is because of the following factors :
i. Large size : The size of these countries adjoining each other together is as large as a continent. India along with its neighbours cover an area of about 52,00,000 sq. km.

ii. Similarities in physiography : Usually the continents are surrounded by water entirely or on three sides. India along with its neighbours is surrounded by water on three sides, which is similar to that of continents. Also, like continents, Indian subcontinent contains all kinds to topographic regions like mountains, plateaus, plains, deserts, valleys etc.

iii. Similarities in climate : Like a continent, the Indian subcontinent has a number of climates in the different parts of the huge landmass. There are regions of heavy snowfall to regions of tremendous heat. The driest and wettest places of Asia also lie within this region. The variations in climate in different topographical regions make it similar to that of a continent.

iv. International rivers : Continents often have rivers that flow within two or more countries. In the Indian subcontinent, the Indus flows through India and Pakistan, the Brahmaputra originates in Tibet, flows through India and Bangladesh, and the Ganga also flows through India and Bangladesh.

v. Culture : Like a continent, the Indian subcontinent exhibits a large variety in caste, creed, colour, language, food habits, housing, religion, economic activities, etc. of people. Ancient civilisation of Mohenjo Daro and Harappa also belong to this region.

Thus, it is rightly said that the region is a subcontinent, and a mini representation of the entire world.

Multiple Choice Questions (MCQ) : 1 Mark

Question 1.
India lies :
(A) mainly in the northern hemisphere
(B) entirely in the northern hemisphere
(C) on the equator
(D) more in the southern hemisphere
Answer:
(B) entirely in the northern hemisphere

Question 2.
The Arabian Sea lies to :
(A) north-east of India
(B) south-east of India
(C) south-west of India
(D) north-west of India
Answer:
(D) north-west of India

Question 3.
Palk Strait separates India from :
(A) Pakistan
(B) China
(C) Andaman Island
(D) Sri Lanka
Answer:
(D) Sri Lanka

Question 4.
Lakshadweep Islands are situated in :
(A) Arabian Sea
(B) Palk Strait
(C) Indian Ocean
(D) Bay of Bengal
Answer:
(A) Arabian Sea

Question 5.
India’s latitudinal and longitudinal extent, measured in degrees, are almost the same, but its east-west extent, measured in in km, is greater than its north-south extent. This is due to the fact that :
(A) longitudes are not parallel lines
(B) the distance between latitudes remains the same but the distance between longitudes is greatest at the equator and nil at the poles where all longitudes join
(C) all longitudes, with their opposites, form great circles
(D) the earth is not a perfect sphere
Answer:
(B) the distance between latitudes remains the same but the distance between longitudes is greatest at the equator and nil at the poles where all longitudes join

Question 6.
The longest shore-line is along the state of :
(A) Gujarat
(B) Maharashtra
(C) Odisha
(D) Kerala
Answer:
(A) Gujarat

Question 7.
Which of the following States of India do not lie entirely in the Tropical Zone of the earth?
(A) Kerala and Tamil Nadu
(B) Gujarat
(C) Karnataka
(D) Maharashtra and Andhra Pradesh
Answer:
(B) Gujarat

Question 8.
The Indian States which have common borders with Pakistan are :
(A) Gujarat, Himachal Pradesh, Haryana and Jammu and Kashmir
(B) Gujarat, Jammu and Kashmir, Punjab and Rajasthan
(C) Jammu and Kashmir, Haryana, Rajasthan and Punjab
(D) Jammu and Kashmir, Himachal Pradesh, Punjab and Rajasthan
Answer:
(B) Gujarat, Jammu and Kashmir, Punjab and Rajasthan

Question 9.
Which of the following Indian islands lies between India and Sri Lanka?
(A) Elephanta
(B) Nicobar
(C) Rameshwaram
(D) Salsette
Answer:
(C) Rameshwaram

Question 10.
The sun rises in Arunachal Pradesh two hours before it does in Dwaraka in Gujarat. This is because the former is :
(A) higher in elevation than Dwaraka
(B) situated further north than Dwaraka
(C) situated further east (about 30° longitude) than Dwaraka
(D) situated about 30° east of Dwaraka and the earth rotates from west to east
Answer:
(D) situated about 30° east of Dwaraka and the earth rotates from west to east

Question 11.
Which of the Indian States has the maximum number of common borders with other Indian States ?
(A) West Bengal
(B) Madhya Pradesh
(C) Uttar Pradesh
(D) Karnataka
Answer:
(B) Madhya Pradesh

Question 12.
Which one of the following gives the three largest states of India (in terms of geographical area) in the correct descending order?
(A) Madhya Pradesh, Rajasthan, Maharashtra
(B) Uttar Pradesh, Madhya Pradesh, Andhra Pradesh
(C) Madhya Pradesh, Maharashtra, Andhra Pradesh
(D) Madhya Pradesh, Uttar Pradesh, Rajasthan
Answer:
(A) Madhya Pradesh, Rajasthan, Maharashtra

Question 13.
Which one of the states not bisected by the Tropic of Cancer is ?
(A) Odisha
(B) Gujarat
(C) West Bengal
(D) Rajasthan
Answer:
(A) Odisha

Question 14.
Of the following towns which one does not lie in the north of the Tropic of Cancer ?
(A) Allahabad
(B) Patna
(C) Bhopal
(D) Jhansi
Answer:
(A) Allahabad

Question 15.
The southern-most point of Indian territory is in :
(A) Tamil Nadu
(B) Lakshadweep
(C) Trivandrum
(D) Andaman and Nicobar Islands
Answer:
(D) Andaman and Nicobar Islands

Question 16.
At present the number of Union territories in India is :
(A) 6
(B) 7
(C) 8
(D) 9
Answer:
(A) 6

Question 17.
The latitude of Indira point is :
(A) 6° 04’N
(B) 6° 40’N
(C) 6° 45’N
(D) 6° 50’N
Answer:
(C) 6° 45’N

Question 18.
The Redcliffe Line demarcates the boundary between
(A) India and China
(B) India and Pakistan
(C) Pakistan and Afghanistan
(D) India and Afghanistan
Answer:
(B) India and Pakistan

Question 19.
The main basis of the delineation of states and union territories of India was
(A) culture
(B) language
(C) administrative efficiency
(D) dress
Answer:
(B) language

Question 20.
Lakshadweep is located near
(A) Konkan
(B) Coromandel
(C) Malabar
(D) Andhra coast
Answer:
(C) Malabar

Question 21.
The southernmost point of Indian landmass is
(A) Cape Comorin
(B) Kannyakumari
(C) Indira point
(D) Indira kol
Answer:
(C) Indira point

Question 22.
The distance between the northern most point in Kashmir and Kanyakumari covers about-
(A) 20° latitude
(B) 25° latitude
(C) 30° latitude
(D) 35° latitude
Answer:
(C) 30° latitude

Question 23.
India, our motherland, liés to the north of equator between 8°4′ to north latitude –
(A) 51° 2′
(B) 43° 5′
(C) 37° 67′ 53”
(D) 31° 2′
Answer:
(C) 37° 67′ 53”

Question 24.
The territorial waters of India extends upto
(A) 5 nautical miles
(B) 12 nautical miles
(C) 15 nautical miles
(D) 2 nautical miles
Answer:
(B) 12 nautical miles

Question 25.
According to area, the largest state of India is
(A) Madhya Pradesh
(B) Rajasthan
(C) Maharashtra
(D) Uttar Pradesh
Answer:
(B) Rajasthan

Question 26.
The boundary line between India and China is called
(A) Radcliff line
(B) Durand line
(C) Mc Mohan line
(D) Red line
Answer:
(C) Mc Mohan line

Question 27.
The capital of Lakshadweep is
(A) Port Blair
(B) Silvassa
(C) Aigawl
(D) Kavaratti
Answer:
(D) Kavaratti

Question 28.
A state which has two capitals is
(A) Uttar Pradesh
(B) Maharashtra
(C) Punjab
(D) Haryana
Answer:
(D) Haryana

Question 29.
Which of the following Indian State does not lie on Indo-Bangladesh border?
(A) Assam
(B) Mizoram
(C) Manipur
(D) Tripura
Answer:
(C) Manipur

Question 30.
Which of the following is not a Union Territory ?
(A) Pondicherry
(B) Lakshadweep
(C) Arunachal Pradesh
(D) Andaman and Nicobar islands
Answer:
(C) Arunachal Pradesh

Question 31.
Port Blair is situated in
(A) North Andaman
(B) South Andaman
(C) Middle Andaman
(D) Little Andaman
Answer:
(B) South Andaman

Question 32.
Lakshadweep is a group of islands.
(A) 22
(B) 27
(C) 32
(D) 35
Answer:
(B) 27

Question 33.
Which of the following Indian state does not lie on the Indo-Nepal border?
(A) Bihar
(B) Uttaranchal
(C) Sikkim
(D) Himachal Pradesh
Answer:
(D) Himachal Pradesh

Question 34.
Duncan pass lies between
(A) India and Sri Lanka
(B) India and Nepal
(C) North and East Andaman
(D) Andaman and Nicobar
Answer:
(C) North and East Andaman

Question 35.
What separates Daman and Diu ?
(A) Narmada river
(B) Gulf of Khambat
(C) Gir hills
(D) Tapi river
Answer:
(B) Gulf of Khambat

Question 36.
Which of the following Indian state is land locked ?
(A) Andhra Pradesh
(B) Bihar
(C) West Bengal
(D) Kerala
Answer:
(B) Bihar

Question 37.
Where does Aksai Chin lie?
(A) Near Leh
(B) North-east corner of Jammu and Kashmir
(C) Along the Zanskan Mountains
(D) South of Siachen Glacier
Answer:
(B) North-east corner of Jammu and Kashmir

Question 38.
Which of the following countries have the longest international boundary with India?
(A) Bangladesh
(B) Bhutan
(C) China
(D) Pakistan
Answer:
(A) Bangladesh

Question 39.
Which important latitude passes through India ?
(A) Equator
(B) Arctic circle
(C) Tropic of Capricorn
(D) Tropic of Cancer
Answer:
(D) Tropic of Cancer

Question 40.
India lies in the
(A) Northern hemisphere
(B) North-eastern hemisphere
(C) Southerrn hemisphere
(D) South-eastern hemisphere
Answer:
(B) North-eastern hemisphere

Fill in the blanks : 1 Mark

1. The smallest state of India is ________.
2. _______ is the most populous state of India.
3. ________ is the least populous state of India.
4. Number of languages accepted by the constitution of India is________.
5. The central meridian of India is________.
6. The basis of state reformation in 1956 was________.
7. Andhra Pradesh has been parted to form the state of________.
8. SAARC consists of _______ members.
9. The headquarter of SAARC is located at________.
10. _______ is the largest state of India.
11. ________ is the most densely populated state of India.
12. The state reforming commission was established in India in________.
13. India extends for _______ km from east to west.
14. The length of the Indian boundary is ________ km.
15. The word ‘India’ has been derived from the greek word________.
Answer:
1. Goa
2. Uttar Pradesh
3. Sikkim
4. 22
5. 82 \(\frac{1{2\)° E
6. Language
7. Telengana
8. 6
9. Kathmandu
10. Rajasthan
11. Bihar
12. 1953
13. 2933
14. 15,200
15. Indoi

State True or False : 1 Mark

1. The largest district of India is Kachch in Gujrat. [ ]
2. The enclaves of Bangladesh have been joined with the state of Assam. [ ]
3. The north-south extent of India is 3214 km. [ ]
4. Chennal is known as the gateway of India. [ ]
5. The least number of districts is present in the state of Sikkim. [ ]
6. The largest Union Territory of India is the Andaman and Nicobar Islands. [ ]
7. The smallest Union Territory of India is Lakshadweep. [ ]
8. A peninsula is surrounded by water on four sides. [ ]
9. The capital of Jharkhand is Patna. [ ]
10. The capital of the newly formed state of Telengana is Hyderabad. [ ]
11. Nagaland has been declared as a state in 1963 . [ ]
12. Punjab was divided to form the states of Punjab and Haryana. [ ]
13. Kerala was previously known as Mahisoor. [ ]
14. Pondicherry is the smallest Union Territory of India. [ ]
15. Durand line is the border between India and Afghanistan. [ ]
Answer:
1. True
2. False
3. True
4. False
5. True
6. True
7. True
8. False
9. False
10. True
11. True
12. True
13. False
14. False
15. True

Match the following : 1 Mark

Name of border	Lying between countries
i. LOC	(a) India and Bhutan
ii. MC Mohan	(b) India and Nepal
iii. Palk Strait	(c) India and Sri Lanka
iv. Indo-Burma Barrier	(d) India and Afghanistan
v. Radcliff line	(e) India and Pakistan
vi. Purvachal	(f) India and Myanmar
vii. Durand line	(g) India and Bangladesh
viii. Indo-Bhutan	(h) India and China

Answer:

Name of border	Lying between countries
i. LOC	(e) India and Pakistan
ii. MC Mohan	(h) India and China
iii. Palk Strait	(c) India and Sri Lanka
iv. Indo-Burma Barrier	(f) India and Myanmar
v. Radcliff line	(b) India and Nepal
vi. Purvachal	(g) India and Bangladesh
vii. Durand line	(d) India and Afghanistan
viii. Indo-Bhutan	(a) India and Bhutan

Answer in few words : 1 Mark

Question 1.
Name the great mountain wall or the northern boundary of India.
Answer:
The Himalayan range.

Question 2.
In which hemisphere does India lie?
Answer:
North Eastern hemisphere.

Question 3.
Which is the smallest state of India ?
Answer:
Goa.

Question 4.
From which state was Jharkhand formed?
Answer:
Bihar.

Question 5.
Which is the youngest state of India?
Answer:
Telengana.

Question 6.
Which is the smallest Union Territory?
Answer:
Lakshadweep.

Question 7.
Name the countries that bound the north west of India.
Answer:
Pakistan and Afghanistan.

Detailed explanations in West Bengal Board Class 10 Geography Book Solutions Chapter 4 Waste Management offer valuable context and analysis.

WBBSE Class 10 Geography Chapter 4 Question Answer – Waste Management

Answer in short : 2 Marks

Question 1.
What do you mean by waste ?
Answer:
‘Waste’ refers to items that we don’t need and we discard. They may be harmful to the environment and are non-usable.

Question 2.
Name some types of wastes.
Answer:
Some types of wastes are : solid wastes, liquid wastes, gaseous wastes, toxic wastes, non-toxic wastes etc.

Question 3.
Name some wastes that come from households.
Answer:
Wastes generated in households are remains of vegetables, fruits etc., scales and bones of fishes, polythene packets, broken bottles, plastic containers, tin containers, aluminium foils, excess food items etc.

Question 4.
What are solid wastes?
Answer:
Solid wastes are any type of garbage or rubbish that are generated at home and outside. They may include food wastes, newspapers, broken household and office items, old car tyres etc.

Question 5.
What are liquid wastes ?
Answer:
Liquid wastes include wash waters from homes, cleaning liquids used in industries, waste detergents etc. Sometimes solid wastes are converted to liquids before discarding.

Question 6.
What are gaseous wastes ?
Answer:
Gaseous wastes can result from activities like manufacturing, processing of materials, consumption or other biological processes. Eg- CO₂, SO₂, N₂, NH₃ etc.

Question 7.
What are toxic wastes ?
Answer:
Toxic wastes are hazardous, harmful and poisonous to public health and environment. Eg. Old propane tanks, pesticides, mercury containing equipments, lamps, batteries etc.

Question 8.
What are non-toxic wastes ?
Answer:
Non-toxic wastes are not so seriously harmful to public health and environment. They can be easily decomposed. Eg – Domestic wastes, food left-overs, fruits and vegetable peelings, paper, wastes produced by shops, restaurants and schools.

Question 9.
What do you mean by industrial wastes ?
Answer:
The wastes produced by industries manufacturing glass, leather, textile, food, electronics, plastic, metal products etc. are called industrial wastes.

Question 10.
What are agricultural wastes?
Answer:
Agricultural wastes are typical produced by agricultural activities like horticulture, fruit growing, seed growing, livestock breeding, market gardening etc. Apart from biotic wastes, they also include non-biotic wastes like pesticide containers, out- of-date medicines, cocoa pods etc.

Question 11.
What are the different processes of waste management?
Answer:
The different processes of waste management are – reduction, reuse and recycling.

Question 12.
Name some methods by which waste can be disposed.
Answer:
The various methods by which wastes can be disposed are – (i) Dumping on open grounds, (ii) Burning, (iii) Landfilling, (iv) Composting, (v) Manure pit, etc.

Question 13.
What are hazardous wastes?
Answer:
The wastes that harmed the environment and the biotic world dangerously, are called hazardous wastes. Ex – (i) Harmful chemical, (ii) Radio-active wastes, (iii) Infected items discarded from hospitals, etc.

Question 14.
Name some diseases that can spread from solid wastes.
Answer:
Some diseases that can spread from solid wastes are – dysentry, skin diseases, worms, typhoid, tuberculosis, jaundice, tetanus, hepatitis, eye diseases, lung diseases etc.

Question 15.
What do you mean by bio-degradable wastes?
Answer:
The wastes that can be reduced and degraded easily by biological entities are called bio-degardable wastes. Generally, the plant and animal wastes are biodegradable. Ex-Proteins, nucleic acids etc. can be degraded by certain bacteria.

Question 16.
What are non bio-degradable wastes ?
Answer:
The wastes that cannot be reduced or degraded by any biological entity are called non bio-degradable wastes. Ex.- Plastic, glass, polythene etc.

Question 17.
What do you mean by waste management?
Answer:
Waste management is the method of collecting wastes scientifically, segregating them, taking steps for recycle, re-use and reduction, so that the ultimate damage or pollution caused by the wastes comes down to minimum.

Question 18.
What is dumping ?
Answer:
Dumping is the process of discarding wastes (usually from large municipal regions) in a lowland, a little away from the main city.)

Question 19.
What are nuclear wastes?
Answer:
The wastes generated from nuclear reactors, raw materials used in nuclear plants, radio-active elements discarded from nuclear plants, etc. are called nuclear wastes. They are highly reactive and very dangerous.

Question 20.
What is Pyrolysis ?
Answer:
The process by which fuel is obtained from solid wastes by processing them in absence of oxygen, is called pyrolysis.

Question 21.
Name four bio-degradable wastes.
Answer:

1. Vegetable peels
2. Bones of fishes and meat
3. Pieces of newspaper
4. Pieces of cotton cloth.

Question 22.
Name two infectious diseases.
Answer:
(i) Influenza, (ii) Hepatitis – B.

Question 23.
What is Landfilling ?
Answer:
The mehtod of discarding wastes in approved grounds, filling up the huge holes dug to bury the wastes, is called Landfilling.

Question 24.
What is Composting ?
Answer:
The bio-degradable wastes are separated and reduced by machines. Then they are degraded with the help of bacteria in order to create humus. The way biotic material produced is called compost, and the process of preparing this is called composting.

Question 25.
What are the most common bad effects of wastes ?
Answer:
Wastes spread bad smell and cause environmental pollution. They help to spread infectious diseases.

Answer in brief : 3 Marks

Question 1.
Name some sources of wastes.
Answer:
Some sources that generate wastes are :

1. Household, hospitals, markets, municipalities etc.
2. Small business centres.
3. Discarded materials from non-producing or abundant factories.
4. Construction materials.
5. Agriculture and food processing.
6. Atomic research centres etc.

Question 2.
Differentiate between toxic and non-toxic wastes.
Answer:

Toxic wastes	Non-toxic wastes
i. Amount of toxic wastes in the environment is less (10%).	i. Amount of non-toxic wastes in the environment is more (90%).
ii. They usually come from hospital wastes, old propane tanks, pesticides, lamps, batteries etc.	ii. They usually come from households.
iii. They are harmful and poisonous.	iii. They are not poisonous and are less harmful.
iv. They may cause infectious diseases. Toxic wastes	iv. They usually do not cause infections. Non-toxic wastes

Question 3.
Differentiate between bio-degradable and non-biodegradable wastes.
Answer:

Bio-degradable wastes	Non-biodegradable wastes
i. Complex biotic materials are converted to simple biotic materials.	i. Wastes cannot be converted to simple substances.
ii. Generated from plant and animals wastes.	ii. Generated from sources other than plants and animals.
iii They are degraded by microorganisms like bacteria.	iii. They are degraded by high temperature and pressure.
iv. Eg-wood, paper, kitchen wastes, food remains etc.	iv. Eg-polythene, PVC, pastic, DDT etc.

Question 4.
What are ‘manure pits’?
Answer:
‘Manure pits’ are hollows dug in the ground in rural areas in order to decompose bio-degradable wastes. The household wastes are thrown into these pits along with some cowdung. These wastes start decomposing and are converted into biotic manure that are used for agriculture.

Question 5.
What do you mean by landfilling ?
Answer:
Landfilling is the most common method of waste disposal, where the waste is buried underground. But this method is not much in use in modern days, as this required a huge vacant land for this purpose, produces strong methane and other gases and cause contamination problems.

Question 6.
Mention some cases where solid wastes are recycled.
Answer:
Solid wastes recycling helps in conservation of resources, controls environmental pollution and also reduces the cost of production. some examples of recycling soild wastes are :

1. Fly ash : Fly ash generated in thermal power stations are used for producing cement, filling up low lands and building low dams.
2. Fibres of sugarcane, agricultural wastes etc. : These are used to produce pulp for paper industies.
3. Plastic, metals, glass, paper etc. : These are melted or processed to be used as raw materials in the respective industries.

Question 7.
Name the methods by which waste materials can be managed and put to use.
Answer:
The main methods of waste management are :

1. Reduction : This refers to the process of waste minimisation at the source itself.
2. Re-use : Items like packing boxes, papers, toys, old clothes etc. can be used again and again, thus saving raw materials, money, controlling pollution and environmental degradation.
3. Recycling : This refers to processing of used materials into new useful products, thus saving raw materials and resources. Eg – paper, metal, plastic and glass items.

Question 8.
What is the need for waste management ?
Answer:
A proper waste management system is urgently needed for the following reasons –

1. To control different types of pollution.
2. To stop the spread of infectious diseases.
3. To conserve environmental resources including forests, minerals, water etc.
4. To recycle hazardous wastes for further production.

Question 9.
What are the advantages and disadvantages of Sanitary landfill?
Answer:
Advantages –

• The wastes are buried underground. Hence they spread less air pollution.
• The gases emitted in this process are used to prepare fuels.
• Biotic fertilisers are obtained by composting of the biotic wastes under pressure.

Disadvantages –

• By landfilling, the polluted water from the wastes gradually percolate underground and get mixed with ground water.
• Disposal of wastes in lowlands hamper the ecosystem and reduce agricultural lands.

Question 10.
What do you mean by Bio-remediation?
Answer:
Bio-remediation is the newest method of waste management. This is the method where bio-technology is used to generate several microbes and fungi. These are applied on biotic wastes so that they can be reduced to the lowest forms. This is a faster process of reducing biotic wastes. It was first applied in 1990 . But the method is not absolutely perfect and suitable for waste management. Ex.- This method is not applicable for all kinds of biotic wastes. Also, the oxygen, nitrogen, phosphorus and other chemicals required by the microbes have to be supplied artificially from outside.

Question 11.
What is Sludge?
Answer:
Different kinds of solid wastes get deposited in drains and sewage pipes, especially in municipal areas. The huge pieces of solid wastes are filtered out with nets. The pieces that are suspended in the sewage water are transfered to large tanks. Calcium carbonate is added to this sewage water, by which the suspended solid wastes settle down at the bottom of the tanks. These deposits at the bottom of the tanks is known as Sludge.

Question 12.
What do you mean by re-use of wastes?
Answer:
The way that the wastes can be used once again in some productive and useful way is called Re-use of wastes. Example of Re-use of wastes can be listed as follows –

1. Biotic fertilisers and biogas : Vegetable peels and other biotic wastes from households and localities can be used to produce bio-fertilisers and biogas.
2. Sugarcane fibre: Huge amounts of sugarcane fibre are re-used to produce paper pulp for paper industries.
3. Old newspapers : Old newspapers, books and copies can be used to produce paper pulp for paper, cardboard, etc.
4. Plastic : Old plastic items can be melted to produce new plastic items.
5. Glass : Discarded glass can be re-used to make new glass. It is also used as a substitute of asphalt.
6. Fly ash : Fly ash can be used for filling up low lands and making bricks.

Question 13.
What do you mean by recycling?
Answer:
The method by which old items are used once again to produce the same item is called recycling. Ex-paper, glass, plastic, metals etc. But the materials produced after recycling is lesser in amount than the initial waste material used.

Question 14.
What is Scrubber? Or what is Scrubbing?
Answer:
Scrubbing is the process of removal of wastes from gases. The gases filled with solid wastes are passed through water. This makes the waste particles wet and heavy. Thus they gradually settle down at the bottom of the containers and waste free gas/air is released. Scrubbing is useful for removing suspended solid wastes from gas/air upto 99 \%.

Answer in details : 5 Marks

Question 1.
Classify the different kinds of wastes.
Answer:
Different types of wastes are as follows:
(i) Solid wastes : Solid wastes are any type of garbage or rubbish generated at home or outside. Eg- food wastes, newspaper, broken household articles etc.
(ii) Liquid wastes : Liquid wastes include wash waters from homes, cleaning liquids used in industries, waste detergents etc. Sometimes, solid wastes are converted to liquids before discarding.
(iii) Gaseous wastes : Gaseous wastes include CO₂, SO₂, N₂O, NH₃ etc. produced as a result of manufacturing activites, consumption and other biological processes.
(iv) Toxic wastes : Toxic wastes are harmful and hazardous poisonous wastes that threaten public health and environment. Eg – pesticides, mercury containing equipments, lamps, batteries etc.
(v) Non-toxic wastes: These wastes are not poisonous as such and do not pose a serious problem to the environment. They can be decomposed easily. e.g. domestic wastes, food left-overs, paper, glass etc.

Question 2.
What are the different sources of wastes?
Or
Classify wastes according to their sources.
Answer:
Wastes can be classified according to sources as :
(i) Domestic wastes : These are wastes generated by household activities. Eg – food left-overs, empty containers, carry bags etc.
(ii) Industrial wastes: These are wastes produced by manufacture works in industries like glass, leather, textile, food, electronics, plastic, metal etc.
(iii) Agricultural wastes: These are typically produced by agricultural activities like horticulture, fruit growing, seed growing, livestock, breeding, market, gardening etc. Non-biotic wastes like pesticide containers, out-of-date medicines etc. are also generated.
(iv) Municipal wastes: These include trash or garbage from households, schools, offices, markets, restaurants and other public places.
(v) Organic wastes : These wastes come from animal or plant sources. EgVegetable peels, garden trimming etc.
(vi) Bio-medical wastes: These wastes come from hospitals and clinics. Egused injection syringes, cotton, bandages, surgical items, body parts etc.
(vii) Radioactive wastes: These wastes contain radioactive materials generated as by-products of nuclear power generation. Eg-Buring of uranium fuel in nuclear reactors.

Question 3.
Discuss the effects of waste disposal on the environment.
Answer:
The effects of waste disposal on several parts of the environment are discussed below :
(a) Effect of solid wastes : (i) Solid wastes lying on ground for a long time pollutes the soil and water of the region. (ii) Diseases like typhoid, jaundice, cholera, dysentery, titanus, skin problems, worms, lung diseases etc. may spread.
Bad smell may spread and cause air pollution.

(b) Effect of toxic wastes : (i) Toxic materials cause air, water and soil pollution. (ii) Toxic materials spread into the food web and enter our bodies causing nerve diseases, kidney problems, tumours, genetic problems, cancer, ulcer etc.

(c) Effect of chemical wastes : Chemical wastes coming from pesticides, insecticides etc. tend to reduce nitrogen content of soil, thus reduce fertility. (ii Numerous animals and birds may get killed. (iii) Land may become totally unproductive.

(d) Effect on water : Accumulation of wastes in rivers, lakes, ponds, oceans, etc. causes death of numerous aquatic plants and animals. (ii) Fishes loose reproductive capacities. (iii) Water ecosystems may get disrupted.

(e) Effect on air : Air pollution increases in alarming rates.

(f) Effect on soil : (i) Wastes disposed on grounds change the chemical properties of soils. (ii) Soils may become acidic and salty and unfit for vegetation growth.

Question 4.
Discuss the methods of waste management.
Answer:
The common methods of waste management are :
(i) Reduction : This is a process of waste minimisation at the source itself, and elimination of harmful and persistant wastes. This involves re-designing of products in order to reduce production of wastes at home, work or other places.
(ii) Reuse : To reuse is to use an item again after it has been used before. Reuse helps to save time, money, energy and resouces. Eg- packing boxes, gift wrapers, toys etc.
(iii) Recycling : Recycling is processing used materials into new, useful products. It helps to save raw materials, energy and money and controls pollution and environmental degradation. Eg – newspaper, metal and glass items etc.

Question 5.
Discuss the several processes of waste disposal and management.
Answer:
The different processes of waste disposal and management are :
(i) Segregation of wastes : Separation of wastes at source of collection is known as segregation of wastes. This reduces the cost of transportaion, energy and helps in acquiring organic stock for energy generation. Wastes may be categorised as: (a) Bio-degradable : Kitchen wastes, garden trimmings, paper etc. (b) Non-biodegradable : Plastics, glass, old medicines, containers etc.

(ii) Landfilling : This is the most common and old method of waste disposal where the waste is buried underground. But this method is not in much use in modern days as it requires huge vacant lands, produces strong methane and other gases and cause contamination problems.

(iii) Composting : This is the process by which unsafe organic wastes are turned into safe organic products with the help of microbes. Eg – organic fertilisers produced from kitchen and food wastes.

(iv) Drainage method : This is a method of removal of suspended solid waste particles in disposed fiquids or water before it is discharged back to the environment.

(v) Scrubbing : Wet scrubbing is a method of using a liquid to remove solid, liquid or gaseous wastes and pollutants. The scrubbing liquid is sprayed into the disposed gas in a spray chamber. Contact with the spray liquid removes the particulate pollutants of the gas. Dry scrabbing is also a popular method.

Question 6.
What is the need for waste management ?
Answer:
A proper waste management system is urgently required for the following –

1. To control different types of pollution.
2. To control the spread of infectious diseases.
3. To conserve environmental resources like forests, minerals, water etc.
4. To recycle hazardous wastes for further production.

Question 7.
What is the role of students in waste management ?
Answer:
Effective waste management is best achieved at household level, and students can take an active role in this process. They can take up the following steps :
(a) Reduce waste creation : (i) Use towels and ceramic plates instead of paper napkins and disposable plates. (ii) Use biodegradable shopping bags instead of plastic bags. (iii) Use old packing boxes and gift wraps.
(b) Reuse things : (i) Use old clothes from elders. (ii) Use old toys, gift wraps, furniture etc. (iii) Innovative use of discarded items. Eg – penstand out of soda cans.
(c) Cleaning programmes : (i) Awareness camps and demonstration programmes regarding garbage disposal.(ii) School can arrange groups of students for regular survery, whether the local people are following cleaning and garbage disposal systems or not.

Question 8.
Discuss the effects of waste disposal in the Bhagirathi- Hooghly river.
Answer:

Waste disposal in huge amounts in the Bhagirathi – Hooghly river pollutes the water in alarming scales. The main sources of pollutants are :

1. Disposal of sewage waters from large cities located on the river side.
2. Disposal of wastes from industries.
3. Agricultural wastes from chemical fertilisers, insecticides etc.
4. Washing of animals, disposal of dead bodies, toilets etc. in river water.
5. Immersion of idols, washing clothes and utensels etc. in river water.
6. Disposal of hot water from thermal power stations etc.

All these actions make the river water impure, which is unhygenic for drinking, domestic, agricultural or industrial use.

Multiple Choice Questions (MCQ) : 1 Mark

Question 1.
The method of using a liquid to remove wastes is called –
(A) Composting
(B) Scrubbing
(C) Dumping
(D) Landfilling
Answer:
(A) Composting

Question 2.
The primary treatment of wastes removes about _______ % of suspended solids from the water –
(A) 20 %
(B) 30 %
(C) 60 %
(D) 70 %
Answer:
(C) 60 %

Question 3.
4R factor for waste management are –
(A) Reproduction-Response-Recover-Record
(B) Reduce-Refuse-Reuse-Recycle
(C) Regenerate-Renew-Reintroduce-Restart
(D) Repeat-Reforms-Reuse-Reproduction
Answer:
(B) Reduce-Refuse-Reuse-Recycle

Question 4.
Hazardous and harmful wastes are called –
(A) Non-toxic
(B) Solid
(C) Toxic wastes
(D) None of these
Answer:
(C) Toxic wastes

Question 5.
The wastes those come from plant or animal sources are called –
(A) Inorganic wastes
(B) Industrial wastes
(C) Organic wastes
(D) Radioactive wastes
Answer:
(C) Organic wastes

Question 6.
Food wastes, fruit and vegetables peels, garden triminings etc. are-
(A) Industrial wastes
(B) Inorganic wastes
(C) Bio-medical wastes
(D) Organic wastes
Answer:
(D) Organic wastes

Question 7.
The liquid that forms as water trickles through contaminated areas is called-
(A) Leachate
(B) Gaseous wastes
(C) Solid wastes
(D) Industrial wastes
Answer:
(A) Leachate

Question 8.
Plastics, glass, old medicines, bulbs, cans etc. are examples of –
(A) Bio-degradable
(B) Non-biodegradable
(C) Organic wastes
(D) Bio-medical wastes
Answer:
(B) Non-biodegradable

Question 9.
Leachate is –
(A) Very healthful mixture of chemicals
(B) Very useful mixture of chemicals
(C) Very resourceful mixture of chemicals
(D) Very harmful mixture of chemicals
Answer:
(D) Very harmful mixture of chemicals

Question 10.
Kitchen wastes, garden trimmings, paper etc. are examples of –
(A) Non-biodegradable
(B) Bio-degradable
(C) Solid wastes
(D) Gaseous wastes
Answer:
(B) Bio-degradable

Question 11.
The place where the waste is buried underground-
(A) Composting place
(B) Landfilling
(C) Segregation of waste
(D) Drainage method
Answer:
(B) Landfilling

Question 12.
Secondary waste treatment removes about –
(A) 30 % of the waste
(B) 50 % of the waste
(C) 70 % of the waste
(D) 90 % of the waste
Answer:
(D) 90 % of the waste

Question 13.
Burning of Uranium in nuclear reactors create –
(A) Radioactive
(B) Toxic
(C) Biomedical wastes
(D) None of these
Answer:
(A) Radioactive

Question 14.
Separation of wastes at source of collection is known as –
(A) Landfilling of wastes
(B) Segregation of wastes
C) Composting of wastes
(D) Scrubbing
Answer:
(B) Segregation of wastes

Question 15.
Useless things, produced in everyday life is known as –
(A) Garbage
(B) Rubbish
(C) Wastes
(D) Pollutant
Answer:
(C) Wastes

Question 16.
DDT, chemical fertilizers, fungicides weedicides etc. examples of –
(A) Biological wastes
(B) Industrial wastes
(C) Chemical wastes
(D) Municipal wastes
Answer:
(C) Chemical wastes

Question 17.
Among biomedical wastes the amount of infectious wastes is –
(A) About 20-22 %
(B) About 30-32 %
(C) About 10-12 %
(D) About 5-10 %
Answer:
(C) About 10-12 %

Question 18.
An example of Bio-nonanalytical organic material is –
(A) Protein
(B) Glass
(C) Nucleic Acid
(D) None of these
Answer:
(B) Glass

Question 19.
The depth of the soil layer above the sanitary landfill is –
(A) 2 metre
(B) 3 metre
(C) 4 metre
(D) 6 metre
Answer:
(A) 2 metre

Question 20.
It takes time to become organic or bio-fertilizer in manure pit –
(A) 2-4 months
(B) 3-4 months
(C) 4-5 months
(D) 1 year
Answer:
(A) 2-4 months

Question 21.
Fungus can be used as-
(A) Control of pests
(B) Weedicide
(C) Element of improving land fertility
(D) None of these
Answer:
(B) Weedicide

Question 22.
Every year amount of land in the world being transformed into desert –
(A) 80 lakh hectare
(B) 30 lakh hectare
(C) 40 lakh hectare
(D) 20 lakh hectare
Answer:
(C) 40 lakh hectare

Question 23.
Main cause of concern on impact in extensive agriculture is –
(A) Chemical fertilizer
(B) Pesticide
(C) Irrigation
(D) Capital
Answer:
(B) Pesticide

Question 24.
Integrated Pest Management is –
(A) Control of pests by chemical pesticides
(B) Destruction of pest infested plants
(C) Integrated application of different methods of pest control
(D) None of the above
Answer:
(C) Integrated application of different methods of pest control

Question 25.
In the biological control process of pests –
(A) Biofertilizer is used in agriculture
(B) Bacteria, virus, fungus
(C) Use of weedicides of control crop pests
(D) None of the above
Answer:
(B) Bacteria, virus, fungus

Question 26.
The full form of NCEP –
(A) National Commission for Environmental Protection
(B) National Committee on Environment Planning
(C) National Committee on Environment Protection
(D) None of the above
Answer:
(B) National Committee on Environment Planning

Question 27.
The permissible limit of pH in drinking water is –
(A) 6.5 – 8.5
(B) 3.5 – 5.5
(C) 4.5 – 6.5
(D) 7.5 – 8.5
Answer:
(A) 6.5 – 8.5

Question 28.
The Government of India had set up a separate ministry for environment for environment in the year –
(A) 1980
(B) 1975
(C) 1990
(D) 2000
Answer:
(A) 1980

Fill in the blanks : 1 Mark

1. The bombing on Hiroshima-Nagasaki is an example of _______ wastes.
2. Old newspaper is a _______ waste.
3. The landfill process leads to the formation of _______ gas.
4. In a scrubber, the wastes one managed by _______.
5. Black foot disease occurs due to _______ pollution.
6. Pesticide is an _______ waste.
7. _______ is celebrated as world Environment Day.
8. The use of already discarded wastes is termed as _______.
9. _______ wastes can be managed by decomposition by microorganisms.
10. _______ is the process of disposing wastes in large pits dug in the ground.
11. _______ wastes are used to produce fuel gas.
12. _______ is used to make paper.
13. A sharp medical waste is _______.
14. Motor oil is a _______ waste.
15. The atomic energy plants generated _______ waste.
16. The animal remains is a _______ waste.
17. Fly ash is a _______ waste.
18. Radium is a _______ waste.
19. Water coming out after washing wastes in landfall method is called _______.
Answer:
1. Radioactive
2. Biodegradable
3. Ammonia
4. Friction
5. Arsenic
6. Agricultural
7. 5th June
8. Re-use
9. Biodegradable
10. Land filling
11. Biotic
12. Sugarcane
13. Surgical knife
14. Liquid
15. Radioactive
16. Biotic
17. Hazardous
18. Radioactive
19. Leachate

State True or False : 1 Mark

1. Minimising the amount of wastes is called reduction. [ ]
2. Electronic wastes are also called e-wastes. [ ]
3. BOD refers to Biological Oxygen Demand. [ ]
4. Sorting of dry and moist wastes is called extraction. [ ]
5. Radiation coming from X-ray machines do not cause radioactive pollution. [ ]
6. Fluoride overuse leads to fluorosis. [ ]
7. Disposal of wastes on high open lands is called dumping. [ ]
8. The Central Ganga Authority was formed in 1985. [ ]
9. Fly ash came from hydel power stations. [ ]
10. Infectious wastes come from hospitals. [ ]
Answer:
1. True
2. True
3. True
4. False
5. False
6. True
7. False
8. True
9. False
10. True

Answer in few words : 1 Mark

Question 1.
What are wash-waters from homes and industries, cleaning liquid etc. called ?
Answer:
Liquid wastes.

Question 2.
What are hospital and clinical wastes called ?
Answer:
Biomedical wastes.

Question 3.
What are wastes coming from plants and animals called ?
Answer:
Organic wastes.

Question 4.
What is Municipal wastes ?
Answer:
Garbage coming from households, schools, offices, markets, restaurants etc.

Question 5.
Name a toxic waste material.
Answer:
Mercury.

Question 6.
Give an example of non-biodegradable material.
Answer:
Polythene.

Question 7.
Name a source of air pollution.
Answer:
Burning of dangerous wastes.

Question 8.
What kind of wastes are radioactive materials ?
Answer:
Toxic wastes.

Detailed explanations in West Bengal Board Class 10 Geography Book Solutions Chapter 3 Hydrosphere offer valuable context and analysis.

WBBSE Class 10 Geography Chapter 3 Question Answer – Hydrosphere

Answer in short : 2 Marks

Question 1.
What are ocean currents?
Answer:

A continuous and regular horizontal movement of ocean water in a fairly defined direction over a great distance on the surface or sub-surface of the ocean is called ocean currents.

Question 2.
How many types of ocean currents are there?
Answer:
There are two types of ocean currents : warm current and cold current.

Question 3.
What is a Sargasso sea ?
Answer:
In the North Atlantic Ocean, the warm gulf current, the cold canary current and the warm north equatorial current flow in a circular pattern.
The water trapped in between these currents remains still and stagnant. A vast growth of moss and other small plants are seen here.This region is known as the Sargasso sea.

Question 4.
What are sand bars?
Answer:
When the warm and cold currents meet, the icebergs being carried by the cold current melts and the sand, pebbles etc. that were within the iceberg gets deposited at the base, creating sand bars. These are economically very useful, as low depth of the sea near the sand bars attract much fishes that are easily acquirable.

Question 5.
Mention two advantages of ocean currents.
Answer:
(i) Ocean currents help in navigation of ships.
(ii) A huge amount of planktons are available in the region where warm and cold currents meet. These attract huge amount of fishes and help in growing of fishing grounds.

Question 6.
Mention two disadvantages of ocean currents.
Answer:
(i) The meeting of warm and cold currents gives rise to huge amount of fog and may create stormy weather.
(ii) The icebergs that flow along with cold currents create a lot of trouble for sailing ships.

Question 7.
What is a tide?
Answer:
The sea water rises in the gulfs and at sea-coasts regularly twice a day at regular intervals. This periodic phenomena of alternate rise and fall in level of the seas is known as Tides.

Question 8.
Mention the causes of tides.
Answer:
The causes of tides are :

1. Gravitational pull of the moon.
2. Effect of Centrifugal force due to rotation of the earth.
3. Gravitational pull of the sun.

Question 9.
What are sea waves?
Answer:
The vertical movement of sea water due to force exerted by wind blowing on the surface, without any horizontal displacement of the water particles is called sea waves. In sea waves, the water moves only up and down.

Question 10.
What are the different controlling factors of ocean currents?
Answer:
The controlling factors of ocean currents are :
(i) Wind, (ii) rotation of the earth, (iii) temperature, density and salinity of ocean water and (iv) presence and location of landmasses.

Question 11.
How does wind cause ocean currents ?
Answer:
The planetary winds blowing over the oceans in fixed directions throughout the year are the main causes of ocean currents. The winds push the water of the oceans in particular directions creating currents. About 2-4% of wind energy is used to create ocean currents. Eg.- The monsoon winds control the flow of ocean currents in the Indian Ocean.

Question 12.
Which ocean shows seasonal reversal of ocean currents and why?
Answer:
The Indian Ocean shows seasonal reversal of ocean currents. Due to the commencement of monsoon winds, the ocean currents flow from south to north and during retreat of the monsoon winds the currents flow from north to south. Thus, there is a 180° reversal of flow of ocean currents during the season change.

Question 13.
What is an ‘Ice wall’?
Answer:
In the Atlantic ocean, near the islands of Newfoundland, the deep green water of the cold Labrador current coming from the north, pass the deep blue water of the warm gulf stream side by side. The boundary of these two currents can be seen very clearly, which looks like an ice wall.

Question 14.
Name two famous sand bars of the world.
Answer:
(i) Grand Bank near Newfoundland in North America.
(ii) Dogger’s Bank in the British Isles of England.

Question 15.
What is the gulf stream ?
Answer:

The part of the North Atlantic current that crosses the Carribean sea and Gulf of Mexico, is called the Gulf stream. It is a warm current (27°C) of deep blue waters.

Question 16.
What is the Grand Bank?
Answer:
Grand Bank is a huge sandbar created near Newfoundland in North America in the northwestern part of the Atlantic Ocean. It is about 96,000 sq . km. in area and its depth is less than 90 ~m. It is a famous fishing ground of the world.

Question 17.
What is the Labrador current?
Answer:

• Labrador current is the ocean current generated from the Arctic ocean due to the polar winds.
• This cold current flows along the western coast of Greenland (between Greenland and Canada) towards the south and flows further to the south along the eastern coast of Labrador Peninsula.

Question 18.
Name some important warm currents of the North Atlantic ocean.
Answer:
Some important warm currents of the North Atlantic Ocean are : (i) North Equatorial current, (ii) Carribean current, (iii) Gulf Stream, (iv) North Atlantic current, (v) Norway current etc.

Question 19.
Name some important cold currents of the North Atlantic Ocean.
Answer:
Some important cold currents of the North Atlantic ocean are : (i) Labrador current, (ii) Eastern Greenland current, (iii) Canary current, (iv) Arctic current etc.

Question 20.
Name some important warm currents of the South Atlantic Ocean.
Answer:
Some important warm currents of the South Atlantic Ocean are : (i) South Equatorial current, (ii) Brazil current, (iii) Guinea current etc.

Question 21.
Name some important cold currents of the South Atlantic Ocean.
Answer:
Some important cold currents of the South Atlantic Ocean are : (i) Antarctic current, (ii) Benguela current, (iii) Folkland current etc.

Question 22.
Name the different warm currents of the Pacific Ocean.
Answer:
Some warm currents of the Pacific ocean are : (i) East Australian current (ii) North and South Equatorial current (iii) Kuroshio current (iv) North Pacific current (v) Alaska current etc.

Question 23.
Name the different cold currents of the Pacific Ocean.
Answer:
The cold currents of the Pacific Ocean are : (i) Antarctic current (ii) Humbolt current (iii) California current (iv) Bering current (v) Kamchatka current etc.

Question 24.
Name some important warm currents of the Indian Ocean.
Answer:
Some important warm currents of the Indian Ocean are : (i) North Equatorial current (ii) South Equatorial current (iii) Madagascar current (iv) Agulhas current (v) Somali current etc.

Question 25.
Name some important cold currents of the Indian Ocean.
Answer:
Some important cold currents of the Indian Ocean are : (i) Antarctic Ocean current (ii) West Australian current etc.

Question 26.
Which currents meet near the Japan coast that helps in creation of fishing grounds?
Answer:
The warm Kuroshio current and the cold Kurile current meet near the coast of Japan, that helps in the formation of fishing grounds.

Question 27.
How does the temperature of ocean water influence the flow of ocean currents?
Answer:
Temperature of ocean water influences the flow and direction of ocean currents. The equatorial and tropical regions being warm, make the water of the adjacent ocean warm as well. The water remains lighter and tends to flow outward towards the poles. This vacuum thus created is filled up by incoming cold currents from the polar regions.

Question 28.
Why is the Japan coast prone to cyclones frequently?
Answer:
The meeting of the warm Kuroshio current and the cold Bering current are responsible for occurrence of frequent cyclones on the coast of Japan.

Question 29.
Why does the British Isles coastal region remain frost free while the Labrador coast remains frozen, inspite of both lying on the same latitude?
Answer:
The warm North Atlantic current flowing along the Western coast of the British Isles helps to keep the region frost free inspite of lying on the same high latitudes as the Labrador coast.

Question 30.
What is the importance of the warm gulf stream of the North Atlantic Ocean?
Answer:

1. The Gulf stream creates foggy conditions and storms near the coastal areas of Newfoundland.
2. It keeps the coastal regions of Norway and British Isles frost free.
3. It helps in creation of fishing grounds on the sandbar of Grand Bank near Newfoundland.
4. It helps in navigation and creation of ice walls.

Question 31.
What is a primary tide or Direct tide?
Answer:
The tide produced in front of the moon is called a Direct tide or Primary tide. Ocean water of the earth nearest to the moon are attracted more strongly. It happens when the moon is directly overhead and its strong attraction forces the water to pile up on that place to form high tide.

Question 32.
What is Secondary or Indirect tide?
Answer:
During high tide, piling of water takes place even at the antipode of the side facing direct tides. This is known as secondary or Indirect tide.

Question 33.
What is a Spring tide?
Answer:
Twice in a month, i.e. on New moon and Full moon days, the moon, the earth and the sun come in a straight line. The combined gravitational forces of the sun and moon cause the highest of high tides. This is called a Spring tide.

Question 34.
What is a Neap tide?
Answer:
When the sun and the moon lie at right angles to each other, the gravitational forces of both counteract each other. Thus the tidal range becomes comparatively low. This is called a Neap tide.

Question 35.
What is a Tidal Bore?
Answer:
When a tide enters the narrow and shallow estuary of a river, the front of the tidal wave appears to be vertical, owing to the piling up of water of the river against the tidal wave and friction against the river bed. The steep-nosed tide crest looks like a vertical water of water rushing upstream. This is called a Tidal Bore.

Question 36.
What causes the occurrence of Tidal Bores?
Answer:
Tidal bores may occur due to :

1. Funnel shape of the mouth of the river.
2. Presence of sandbars near the mouth of the river.
3. Tremendous current of the river water.

Question 37.
What is the interval between two high tides?
Answer:
The interval between two high tides is about 12 hours 24 minutes 44.5 seconds.

Question 38.
What is the interval between a high tide and a low tide ?
Answer:
The interval between a high tide and low tide is about 6 hours 12 minutes 22.25 seconds.

Answer in briefly : 3 Marks

Question 1.
Differentiate between waves and ocean currents.
Answer:

Waves	Ocean currents
i. This refers to the upward and downward movement of sea water.	i. This refers to the horizontal movement of sea water.
ii. The water moves up and down but no big displacement of the water occurs.	ii. The water flows through a specific path or direction horizontal to the surface of the sea.
iii. Created due to wind movement, vulcanism, earthquake etc.	iii. Created due to planetary winds, temperature of water, salinity, presence of landmass, rotational speed of the earth etc.
iv. Moves perpendicular to the alignment of coasts.	iv. Moves parallel to the alignment of coasts.
v. Useful for marine erosion and deposition.	v. Useful for carrying away the eroded materials.
vi. Does not influence weather and climate.	vi. Influences weather and climate.

Question 2.
How do prevailing winds influence ocean currents ?
Answer:
Ocean currents are mainly caused by prevailing winds. The planetary winds push the surface layers of ocean water towards a constant flow. If, due to seasonal change, the direction of wind is changed, the currents also have a similar change in their direction.
In Tropical regions, equatorial currents moves from east to west under the influence of trade winds. In Temperate regions, the westerlies drive the sea water from west to east.

Question 3.
What is the influence of difference in temperature of sea water on ocean currents?
Answer:
Temperature is low at the poles and high at the equator. The polar water is cool, heavy and sinks while the equatorial water is warm, light and floats. This sets up convectional currents in the ocean. Warm water of the equatorial regions are light and move along the surface towards the polar regions where they are cooled.

Question 4.
What is the influence of salinity of ocean water in formation of ocean currents?
Answer:
The salinity of ocean water varies from place to place. Water of high salinity are denser than water of low salinity. Hence water of low salinity flow on the surface while water of high salinity flows at the bottom towards water of low salinity.

Question 5.
How does the centrifugal force influence ocean currents?
Answer:
The centrifugal force at the equator is greater than that at the poles. Due to this variation of forces, the equatorial water moves towards the poles.

Question 6.
How does evaporation and rainfall influence ocean currents?
Answer:
Evaporation reduces the amount of water in the ocean and increases salinity. Rain water raises the sea level and reduces salinity. This difference between density of water caused by evaporation and rainfall helps to generate ocean currents.

Question 7.
How does the shape of the continents influence ocean currents ?
Answer:
The ocean currents generally follow the coastline of the continents while flowing. But presence of numerous islands in their way may bifurcate the currents into numerous smaller streams of ocean currents.

Question 8.
What are Primary and Secondary tides?
Answer:
The tides produced on the surface of the earth facing the moon are called primary tides or Direct tides. At the same time, there is a piling of ocean water on the antipode or the opposite side of the earth. These tides are called Secondary or Indirect tides.

Question 9.
What are spring tides?
Answer:
The term Spring tides comes from the German word ‘Springen’, which means to jump. Twice a month, at new moon and full moon, the sun, the earth and the moon fall in straight line. The combined gravitational pull of the sun and the moon causes the highest tides. These are known as Spring tides.

Question 10.
What are Neap tides?
Answer:
Neap tides occur when the sun and the moon lie at right angles to the earth. This happens in the first and last quarters of the moon. The gravitational force of the sun and the moon counteracts each other. The tidal range is neither too high nor too low. These tides are known as neap tides.

Question 11.
What is Syzygy?
Answer:
When the sun, the moon and the earth come along the same straight line, this fact is known as syzygy in astrology. Two types of positions are found in syzygy:
(i) Conjunction : At the time of Full Moon, when the earth comes between the moon and the sun in a straight line the position is called conjunction.
(ii) Opposition : At the time of New Moon, when the moon comes between the earth and the sun in the same line, this position is known as opposition.

Question 12.
What are Perigean tides and Apogean tides?
Answer:

Perigean tides : When the moon is the closest to the earth (354,330 km), this position is known as perigee. The perigee position increases the attracting force of the moon and the tide is extraordinarily high. This is known as Perigean tide.
Apogean tides : When the moon is farthest from the earth (4,03,320 km), this position is known as Apogee. Due to reduced attraction of the moon, the tide is also 20% less high. This is known as Apogean tide.

Question 13.
Mention the characteristics of ocean currents.
Answer:
The characteristics of ocean currents are :

1. The warm currents flow outwards from the equatorial region towards the polar region.
2. The cold currents flow inwards from the polar region to the equatorial region.
3. The ocean currents flow almost in the same direction as the direction of the prevailing winds.
4. Speed of ocean currents is higher in shallow water and slower in deep water.

Question 14.
How does the centrifugal force of the earth influence the creation of tides?
Answer:
Centrifugal force is generated due to the rotation of the earth. Due to this force, all particles tend to move outward in the opposite direction of the gravitational force. Thus, the water present on the earth’s surface always tends to rise and move in the opposite direction of gravitational force. This leads to the creation of tides in different parts of the earth.

Question 15.
Why high tides and low tides each occur twice a day ?
Answer:
The earth (each and every part) faces the moon after every 24 hours 49 minutes 29 seconds. The side that faces the moon experiences direct or primary high tides and the opposite side experiences indirect or secondary high tides. Again, as the earth rotates, the place which experienced primary high tide will now experience secondary high tide and vice versa. The time difference between primary and secondary tides is 12 hours 24 minutes 44.5 seconds. The places lying at right angles to places experiencing high tides will experience low tides. Hence, two low tides occur in each place. Thus we see that both high tides and low tides occur twice a day.

Answer in details : 5 Marks

Question 1.
Discuss the causes of ocean currents.
Answer:

The main causes of the origin of ocean currents are:
(a) Prevailing winds : The planetary winds or prevailing winds push the surface layers of the ocean water in front of them in a constant flow. If, due to a seasonal change, the direction of wind is changed, the currents also have a similar change in their direction. In Tropical areas, the equatorial currents moving along with trade wind move from east to west. In Temperate regions, westerlies drive the sea water from west to east.
(b) Difference in temperature: Temperature is low at the poles and high at the equator. The polar water is cool and becomes heavy and sinks. Te equatorial water is warm, light and floats. This creates a convectional current and the polar water move towards the equator and vice versa.
(c) Difference in salinity : The salinity of ocean water varies from place to place. Water of high salinity are denser than water of low salinity. Hence, water of low salinity flows on the surface while water of high salinity flows at the bottom of the oceans.
(d) Rotation of the earth : The rotation of the earth generates a centrifugal force, which causes generation of currents in the ocean water.
(e) Shape of coasts : The shape and direction of the coasts of the landmasses also change the direction of the currents.
(f) Centrifugal force : The centrifugal force of the earth is greater at the equator than the poles. Hence, water currents move from equatorial region to the poles.
(g) Evaporation and rainfall : Evaporation decreases water level and increases salinity while rainfall increases the water level and decreases salinity. This influences the flow of ocean currents.
(h) Melting of ice : Melting of ice raises the sea level and reduces salinity, influencing the ocean currents.

Question 2.
List the general characteristics of ocean currents.
Answer:
The characteristics of ocean currents are as follows:

1. The general movement of ocean currents is clockwise in the northern hemisphere and anti-clockwise in the southern hemisphere.
2. Warm currents move towards cold seas and cold currents move towards warm seas.
3. In the lower latitudes, the warm currents flow on the eastern shores and cold currents in the western shores. This condition is reversed in the higher latitudes.
4. Convergence and divergence of warm and cold currents influence the direction of flow.
5. The shape and position of continents guide the direction of ocean currents.
6. The currents flow not only at the surface, but also below the sea surface.

Question 3.
What are the effects of ocean currents ?
Answer:
The various effects of ocean currents are:
i. Difference in temperature : The regions where warm ocean currents pass, become comparatively warmer, while the regions where cold ocean currents pass, become comparatively cooler.
ii. Rainfall : Winds crossing warm ocean currents gather enough moisture and cause much rainfall. But winds causing cold currents do not gather much moisture, hence do not cause much rainfall.
iii. Fog and Storms : Regions where warm and cold currents meet remain foggy almost throughout the year and often face storms.
iv. Parity in temperature: The ocean currents help to balance the distribution of heat of the water between higher and lower latitudes. Hence they influence distribution of world temperature.
v. Frost-free harbours : Warm currents help to keep the mouths of the harbours of higher latitudes frost-free even in winters.
vi. Navigation : Ships can move faster and easily along the ocean currents. Movement against the direction of currents is difficult, time consuming and fuel consuming.
vii. Sandbars : When warm and cold currents meet, the icebergs carried by cold currents melt. The sand, pebbles etc. being carried by the icebergs get deposited at the base, creating sandbars. These are economically useful as low depth of the sea in this region attracts much fishes which can be easily acquired.
viii. Business and commerce : Sandbars are good for growth of planktons, which are favourite fish foods. Thus huge number of fishes are attracted to these regions. This leads to a huge catch of fish, naturally leading to good business and commerce.

Question 4.
Discuss the causes of tides.
Answer:

The main causes of tides are –
i. Gravitational pull of the moon : Although both the sun and the moon exert gravitational force on the earth, the sun’s force is only 46 \% of that of the moon due to its large distance from the earth compared to the moon. Hence, the moon’s influence on the tides is twice as strong as that of the sun. The water of the earth nearest to the moon is pulled by its gravitational force. This makes the water on this side bulge, causing high tide. Waters on the opposite side also experience high tides at a comparatively lower scale. The areas perpendicular to these areas experience ebb or low tides.

ii. Effect of centrifugal force or rotation of the earth : Rotation of the earth causes generation of centrifugal force, which tends to throw the waters outwards. This causes the rise of water as tides.
iii. Gravitational pull of the sun : The sun also helps to cause tides. When it lies in the same side as the moon, it causes very big tides. When the sun lies in the opposite direction to the moon, it causes weaker tides.

Question 5.
Discuss the effects of tides.
Answer:
The various effects of tides are :

1. Tidal energy can be harnessed to generate electricity.
2. Fishermen’s activities are controlled by the rhythms of high and low tides.
3. Tidal water helps ships to move in and out of river ports.
4. Tides help to increase depth of channels, lower freezing points at river mouths, help to clear depositions at river mouths and clear sewage from large urban centres.
5. During high tides low lying areas along sea coasts are flooded and this water is trapped for production of salt.
6. Tides aid the destruction of coastline and help to move debris to the sea.
7. Bores are characteristics of certain river mouths, such as those of the Amazon, Colorado, Hooghly and Elbe.
8. When bores are well-developed, the moving wall of water may be 4-5 m high and is reported to be a terrifying and destructive phenomenon.

Question 6.
Why the time difference between two primary high tides of the same place is about 24 hours 49 minutes?
Answer:
The earth takes about 23 hours 56 minutes 48 seconds to complete one rotation. If the moon would have been fixed, the same place of the earth would have experienced primary high tides after every 23 hours 56 minutes 48 seconds. But as the moon is revolving in its orbit in 27 \(\)\frac{1}{3}\(\) days in the same direction due to earth’s rotation, the conditions change. As the speed of earth’s rotation and moon’s revolution are not the same the moon covers (360° ÷ 27 \(\)\frac{1}{3}\(\). day) = 13° 10′ 14.63″ angular distance every day. Therefore, the moon takes extra time of (13° 10’14.63″ × 4. minutes) = 52 minutes 41 seconds to reach the same place once again. For this, the time difference of primary high tides at a particular place of two following days is about 24 hours 49 minutes 29 seconds.

Multiple Choice Questions (MCQ) 1 Mark

Question 1.
Water movement is –
(A) Vertical
(B) Horizontal
(C) Vertical and horizontal
(D) None of these
Answer :
(B) Horizontal

Question 2.
Waves are caused due to –
(A) Winds
(B) The moon and the sun
(C) Tides
(D) Ocean currents
Answer :
(A) Winds

Question 3.
On the new moon, occurs the –
(A) Spring tide
(B) Neap tide
(C) Ebb tide
(D) Low tide
Answer :
(A) Spring tide

Question 4.
Warm ocean currents flow towards the –
(A) Polar regions
(B) Equatorial regions
(C) Tropical regions
(D) Temperate regions
Answer :
(A) Polar regions

Question 5.
At the places where warm and cold currents meet, occurs –
(A) Cyclones
(B) Tides
(C) Clear sky
(D) Dense fog
Answer :
(D) Dense fog

Question 6.
Cold water is seen in –
(A) Pacific Ocean
(B) Atlantic ocean
(C) Indian ocean
(D) Arctic ocean
Answer :
(B) Atlantic ocean

Question 7.
Warm currents flow along the –
(A) Low latitudinal or Equatorial region
(B) Middle latitudinal region
(C) High latitudinal region
(D) Polar region
Answer :
(A) Low latitudinal or Equatorial region

Question 8.
The El-Nino which influences the Indian monsoon is –
(A) A cold ocean current that flows northwards along the coast of Chile
(B) A warm ocean current that flows westwards
(C) A low pressure system over western coast of Spain
(D) None of these
Answer :
(D) None of these

Question 9.
What is the interval between high tides at a place ?
(A) 12 hour
(B) 12 hour 26 minute
(C) 15 hour 30 minute
(D) 24 hour
Answer :
(B) 12 hour 26 minute

Question 10.
The place lying opposite to the moon experiences –
(A) Low tide
(B) Primary tide
(C) Secondary tide
(D) No tide
Answer :
(C) Secondary tide

Question 11.
Neap tide occurs on the – day after the new moon and full moon.
(A) 5 th
(B) 6th
(C) 7 th
(D) 8 th
Answer :
(D) 8 th

Question 12.
The South and North Equatorial currents of Atlantic Ocean move from east to west by the influence of –
(A) Trade winds
(B) Westerlies
(C) Polar winds
(D) Local winds
Answer :
(A) Trade winds

Question 13.
The direction of ocean currents is reversed with seasons in the –
(A) Pacific Ocean
(B) Atlantic Ocean
(C) Indian Ocean
(D) Arctic Ocean
Answer :
(C) Indian Ocean

Question 14.
Average salt content in 1 litre of sea water is –
(A) 39 gm
(B) 37 gm
(C) 35 gm
(D) 32 gm
Answer :
(C) 35 gm

Question 15.
The water in the oceans move horizontally over vast areas due to –
(A) Slope of the sea floor
(B) Waves
(C) Difference in density
(D) Currents
Answer :
(C) Difference in density

Question 16.
The tide at its maximum height is known as –
(A) Primary tide
(B) Neap tide
(C) Spring tide
(D) Ebb tide
Answer :
(C) Spring tide

Question 17.
The factors responsible for the movement of the surface oceanic currents are –
(i) Prevailing winds
(ii) Earth’s rotation
(iii) Earth quake
(iv) Difference in density of sea water
(v) Sea floor topography
(A) i, iii and iv
(B) i, ii and iii
(C) i, iii and iv
(D) None of these
Answer :
(A) i, iii and iv

Question 18.
Dense fog is formed near Newfoundland and Grand Bank due to convergence of –
(A) Cold Labrador current and warm gulf stream
(B) Cold Canary current and warm gulf stream
(C) Cold Labrador current and warm kuroshio current
(D) None of these
Answer :
(A) Cold Labrador current and warm gulf stream

Question 19.
The position of smallest distance between the earth and the moon is called –
(A) Apogee
(B) Perigee
(C) Apogean
(D) None of these
Answer :
(B) Perigee

Question 20.
High tides are caused when –
(A) The sun, earth and moon lie in a straight line.
(B) The sun and moon lie perpendicular to the earth
(C) Both ‘A’ and ‘B’
(D) None of these
Answer :
(A) The sun, earth and moon lie in a straight line.

Question 21.
High tides are caused at the time of-
(A) Fullmoon
(B) New moon
(C) Both ‘A’ and ‘B’
(D) None of these
Answer :
(C) Both ‘A’ and ‘B’

Question 22.
High tides are also called –
(A) Neap tides
(B) Spring tides
(C) Ebb tides
(D) Primary tides
Answer :
(B) Spring tides

Question 23.
The sun, the moon and the earth are in position of opposition during the-
(A) New moon
(B) Full moon
(C) Half moon
(D) Crescent moon
Answer :
(B) Full moon

Question 24.
The position of the sun, moon and earth in a straight line is called-
(A) Syzygy
(B) Quadrature
(C) Opposition
(D) None of these
Answer :
(A) Syzygy

Question 25.
When the earth lies inbetween the sun and the moon, the position is called –
(A) Conjunction
(B) Opposition
(C) Quadrature
(D) None of these
Answer :
(B) Opposition

Question 26.
When the sun, earth and moon lie in a position of right angle, it is called-
(A) Opposition
(B) Conjunction
(C) Quadrature
(D) None of these
Answer :
(C) Quadrature

Question 27.
During neap tides, the sun, earth and moon come in the position of-
(A) Opposition
(B) Quadrature
(C) Syzygy
(D) Conjunction
Answer :
(B) Quadrature

Question 28.
The position of farthest distance between earth and moon is called –
(A) Apogee
(B) Perigee
(C) Conjunction
(D) Opposition
Answer :
(A) Apogee

Question 29.
Cold wall is seen in
(A) Atlantic
(B) Antractic
(C) Indian
(D) Pacific Ocean
Answer :
(A) Atlantic

Question 30.
Which of the following is an warm current ?
(A) Kamchatka
(B) Peru
(C) Brazil
(D) West Australian
Answer :
(C) Brazil

Question 31.
Ocean currents are generated due to
(A) Difference in temparature
(B) Difference in Salinity
(C) Movements of Planetary winds
(D) All the above is correct
Answer :
(C) Movements of Planetary winds

Question 32.
The speed of ocean current in shallow seas compared to deep seas is
(A) More
(B) Less
(C) Not affected
(D) Remain same
Answer :
(A) More

Question 33.
Grand bank is a
(A) Warm Current
(B) Cold Current
(C) Submerged bar
(D) Island
Answer :
(C) Submerged bar

Question 34.
Ocean currents created by
(A) Rotation of the earth
(B) revolution of the earth
(C) Gravitational force
(D) None of these
Answer :
(A) Rotation of the earth

Fill in the blanks : 1 Mark

1. The general movement of a mass of oceanic water in a definite direction is called ________.
2. Okhotsk current is found in the _________ ocean.
3. _______ currents help in the formation of Sargasso sea.
4. _________ current is characterised by high temperature and high salinity.
5. ________ current is also known as Humboldt current.
6. North-east monsoon currents are produced between Andaman and ________.
7. El-Nino is a weather event restricted to certain ________ areas.
8. El-Nino maximum affects the ________ coast.
9. Fall of sea water and its movement towards the sea is called an ________.
10. Each day, tide is delayed by _______ minutes.
11. Perigean tides are ________ percent higher than the normal tides.
12. The coasts of British Isles and Norway remain frost-free due to the influence of the _______ current.
13. The _______ winds control the currents of the Indian Ocean.
14. The largest sand bar of the world is the ________.
15. The Madagascar and Mozambique currents combine to form the ________ current.
16. The warm _________ current keeps the east coast of Japan warm in winter.
17. ________ is created at the meeting points of warm and cold currents.
18. Heavy saline water flows as ________.
19. The average speed of ocean current is ________.
20. ________ is the largest ocean of the world.
21. The colour of water in the ________ current is slightly greenish.
22. The floating blocks of ice in the ocean are called ________.
23. The ice wall can be seen in the _______ Ocean.
24. The Sargasso Sea has been created in the _______ Ocean.
25. Planktons concentrate where ________.
Answer:
1. Ocean current
2. Pacific
3. Artiles
4. Brazil
5. Peru
6. Somali
7. Tropical
8. Peruvian
9. Ebb
10. 26
11. 15-20
12. Warm gulf stream
13. Monsoon
14. Grand Bank
15. Aguthas
16. Kuroshio
17. Fog
18. Under current
19. 5-10 km/ hr.
20. Pacific Ocean
21. Labrador
22. Ice bergs
23. Atlantic
24. Atlantic
25. Warm and Cold Currents meet

State True or False : 1 Mark

1. Benguela current flows through the Indian Ocean. [ ]
2. The ocean curents get deflected due to coriolis force. [ ]
3. The cold oyashio current flows along the coast of Japan. [ ]
4. Grand Bank lies in the Pacific Ocean. [ ]
5. Meeting of warm and cold ocean currents lead to the formation of fog. [ ]
6. Bering current is a cold current in the North Pacific Ocean. [ ]
7. Labrador current is a cold current in the North Atlantic Ocean. [ ]
8. A warm current flowing through the south Pacific Ocean is the New South Wales current. [ ]
9. A cold current flowing through the South Pacific Ocean is the Peru current. [ ]
10. The rising and falling of ocean water is known as ocean current. [ ]
11. The Humboldt current follows the coast of Chile. [ ]
12. The warm gulf stream lowers the temperature of the Eastern coast of North America in winter. [ ]
13. The meeting of the warm Kuroshio current and the cold Oyashio current lead to formation of dense fog and stormy conditions along the Japan coast. [ ]
14. The Western coast of the continents in tropical regions are influenced by cold curents, which lead to lack of rainfall and formation of deserts. [ ]
15. Ebb tides occur on new moon and full moon nights. [ ]
16. Tidal bores occur in the lower course of the river Hugli. [ ]
17. The ocean currents in the southern hemisphere are deflected towards the left due to rotation of the earth. [ ]
18. The Sargasso sea has no current. [ ]
19. Kuroshio current is a warm current. [ ]
20. California current is a cold current. [ ]
21. Foggy weather persist near the cold wall. [ ]
22. Drought occure along the east coast of Pacific ocean under the influence of La Nina. [ ]
Answer:
1. False
2. True
3. True
4. False
5. True
6. True
7. True
8. True
9. True
10. False
11. True
12. False
13. True
14. True
15. False
16. True
17. True
18. True
19. True
20. True
21. True
22. True

Answer in few words : 1 Mark

Question 1.
How much of the earth’s surface is covered by oceans?
Answer:
About 3 / 4 th.

Question 2.
What is the tide caused on full moon called ?
Answer:
Spring tide.

Question 3.
Which ocean currents move towards polar regions ?
Answer:
Warm ocean currents.

Question 4.
What type of ocean currents originate in high latitudes?
Answer:
Cold currents.

Question 5.
Which ocean currents have lighter water ?
Answer:
Warm currents.

Question 6.
Which ocean currents have denser water?
Answer:
Cold currents.

Question 7.
What is the direction of flow of ocean currents in the northern hemisphere?
Answer:
Clockwise.

Question 8.
What is the other name of Low tide?
Answer:
Ebb tide.

Question 9.
How many tides occur in a day?
Answer:
Two high tides and two low tides.

Question 10.
What is the upward and downward movement of ocean water called?
Answer:
Ocean waves.

Question 11.
Which is the main controlling power of the ocean current?
Answer:
Planetary wind.

Question 12.
In which ocean Sargasso sea is seen ?
Answer:
Atlantic ocean.

Detailed explanations in West Bengal Board Class 10 Geography Book Solutions Chapter 2.5 Humidity and Precipitation offer valuable context and analysis.

WBBSE Class 10 Geography Chapter 2.5 Question Answer – Humidity and Precipitation

Answer in short : 2 Marks

Question 1.
What do you mean by ‘Hydrological cycle’?
Answer:
Water is present on the earth’s surface as well as the atmosphere in different forms. This water is transported from one sphere to the other in different forms in a cyclical pattern. This circulation of water from lithosphere (earth’s surface or underground) to atmosphere and back is known as the hydrological cycle. It is mainly driven by evaporation and condensation.

Question 2.
What do you mean by humidity ?
Answer:
Humidity is the general term refering to the water vapour content of air at one time and place. It is the measure of the dampness of the atmosphere.

Question 3.
What is the relation between humidity and temperature ?
Answer:
Humidity capacity or moisture retaining capacity of air is directly related to the temperature condition of the air. Higher the temperature, greater is the water holding capacity of air and vice versa. Hence, cooler air gets saturated faster than hot air.

Question 4.
What do you mean by saturation of air ?
Answer:
Air is said to be saturated when it holds moisture or water vapour to its fullest capacity at that particular temperature.

Question 5.
What do you mean by Absolute humidity ?
Answer:
Absolute humidity refers to the total amount of water vapour present in a given volume of air. It is the weight of actual amount of water vapour present in a unit volume of air. It is measured in gram per cubic centimetre.

Question 6.
What is Relative humidity ?
Answer:
The ratio of the amount of water vapour present in the air mass at a given temperature of a place to the maximum quantity that the air can hold at that particular temperature, is known as relative humidity.

Question 7.
What is Specific Humidity ?
Answer:
Specific humidity is the mass of water vapour in grams contained in a kilogram of air. It represents the actual quantity of moisture in a definite amount of air. It is measured in gram/kilogram.

Question 8.
What is condensation?
Answer:
The process of conversion of atmospheric water vapour back to water is known as condensation. In the atmosphere, they may occur in the forms of dew, fog, smog, cloud, mist, haze etc.

Question 9.
What is the ‘Dew point’ ?
Answer:
The temperature at which air gets saturated and below which condensation begins is called the ‘Dew point’.

Question 10.
What is ‘dew’?
Answer:
The water droplets formed by the condensation of water vapour on a relatively cold surface is called ‘dew’.

Question 11.
What is the difference between fog and smog?
Answer:
Suspended tiny droplets or ice crystals in the air layer next to the earth, that reduce visibility to 1000 m or even lower are called fog. Combination of smoke with fog, which creates a hazy environment, reducing visibility even more, is called smog. It is more common in an industrial areas.

Question 12.
What is cloud?
Answer:
A visible aggregate of tiny water droplets or ice crystals or a mixture of both suspended in the air, are called cloud. It forms when condensation meets with supersaturation conditions within the air that is free from dust and aerosols.

Question 13.
What do you mean by Precipitation?
Answer:
Condensation of water vapour in the air in the form of water droplets and ice, and their falling on the ground is called precipitation. It can occur in the form of rain, snow, sleet, hail etc.

Question 14.
What is rainfall ?
Answer:
When moisture-laden air rises up, condensation takes place and clouds are formed. It the clouds air further cooled, more condensation occurs and drops of water formed are big in size. These big water drops are too heavy to remain in the air and fall down towards the ground in liquid form. This is called rainfall.

Question 15.
What is an isohyet?
Answer:
An isohyet is an imaginary line drawn on a map joining places receiving the same amount of rainfall in a given period, such as a month, a season or a year.

Question 16.
Name the different types of rainfall.
Answer:
There are three types of rainfall-convectional, orographic or relief and cyclonic or frontal rainfall.

Question 17.
Where does convectional rainfall generally occur?
Answer:
Convectional rainfall is very common in the Equatorial region where it occurs almost daily in the afternoon around 4 o’clock. Hence, it is also called the 4 o’clock rain.

Question 18.
What do you mean by climatic regions ?
Answer:
The average weather conditions of a particular region during a particular period of the year, recorded for 35 years is known as climate. Depending on the predominant climate, the world can be divided into several regions. These regions are called the ‘Climatic regions’.

Question 19.
How can you identify wet equatorial climate prevailing in a region?
Answer:
The conditions that prove the existence of wet equatorial climate prevailing in a region are :

1. Average temperature : 25°-29°C
2. Average annual rainfall : 250 cm, rainfall occurs in all the months.
3. Maximum rainfall : occurs in March-April, and September – October.

Question 20.
How can you identify Tropical Monsoon climate?
Answer:
The conditions of Tropical Monsoon climate are :

1. Average annual temperature : 24°C
2. Average summer temperature : 27°-32°C
3. Average winter temperature : 10°-27°C
4. Average rainfall : 100-150 cm
5. Highest rainfall : May to September in northern hemisphere, November to March in southern hemisphere.

Question 21.
How can you identify Tropial Hot Desert climate?
Answer:
The conditions of Tropical Hot Desert climate are :

1. Average annual temperature : 20°-32°C
2. Average annual rainfall : 16-25 cm
3. Hottest months : May to August in the northern hemisphere, November to February in the Southern hemisphere.

Question 22.
How can you identify Mediterranean climate?
Answer:
The conditions of Mediterranean climate are :

1. Average annual temperature : 13°-18°C
2. Average summer temperature : 14°-22°C
3. Average winter temperature : 10°-14°C
4. Average annual rainfall occuring during winter : 35-75 cm

Question 23.
How can you identify Tundra climate?
Answer:
The conditions of Tundra climate are :

1. Average annual temperature : (-) 10°C to (-) 15°C
2. Average annual rainfall : 10-15 cm. Most precipitation occurs in the form of snow.
3. Hottest months : May to August in the northern hemisphere and November to February in the Southern hemisphere.

Question 24.
Mention two characteristics of absolute humidity.
Answer:
(i) Absolute humidity may remain unchanged throughout the day even if Relative Humidity changes.
(ii) Absolute humidity helps to decide the amount of precipitation possible.

Question 25.
Name the instruments that help to measure humidity.
Answer:
Humidity can be measured by the Dry and Wet Bulb Thermometer. It is also measured by a Hygrometer. The common types of Hygrometers used for this purpose are – Dew point Hygrometer, Hair Hygrometer, Resistant Hygrometer etc.

Question 26.
Why is fog and smog more common in urban and industrial areas ?
Answer:
The air over urban and industrial areas is filled with suspended particles of dust, carbon etc. which act as a cool surface for condensation of water vapour. Thus, they cause occurrence of fog and smog much more in urban and industrial areas.

Question 27.
Name the regions of the world that experience Hot Wet Equatorial climate.
Answer:
The regions that experience Hot Wet Equatorial climate are :

1. Amazon basin in Brazil, South America.
2. The Zaire basin, Congo basin, Ivory coast, Ghana, Nigeria in Africa.
3. Malaysia, Indonesia and other islands of South-East Asia.

Question 28.
Name some countries that experience tropical monsoon climate.
Answer:
The countries that experience tropical monsoon climate are – (i) India, (ii) Pakistan, (iii) Bangladesh, (iv) Myanmar, (v) Cambodia, (vi) Thailand, (vii) Laos, (viii) Vietnam etc.

Question 29.
Name some hot deserts of the world.
Answer:
(a) Africa – Sahara, Kalahari
(b) Asia – Arab, Thar
(c) North America – Colorado, Soneran
(d) South America – Atacama, Peru
(e) Oceania – The Great Australian desert

Question 30.
Name some important Temperate grasslands of the world.
Answer:

1. Steppes of Europe and Asia (World’s largest)
2. Prairies of North America.
3. Pampas of South America
4. Veld of Africa
5. Downs of Oceania.

Question 31.
Why is the Equatorial region called ITCZ ?
Answer:
The Equatorial region is called the ITCZ or the Inter Tropical Convergence Zone because the South-Eastern and North-Eastern trade winds meet at the Equatorial region near 5°-10° N and S latitudes.

Question 32.
Why is the Equatorial region called Doldrums?
Answer:
The Equatorial region does not face any wind due to the convergence of the trade winds of both the hemispheres. A condition of calm persists in this region. This is called Doldrums.

Question 33.
Why is Equatorial rainfall also called 4 o’clock rainfall ?
Answer:
The Equatorial region experiences convectional rainfall. The sky remain clear and bright throughout the day. But due to high rates of evaporation, dense cumulonimbus clouds accumulate at about 3-4 o’clock in the afternoon and cause heavy rainfall. Thus, it is also called 4 o’clock rainfall.

Question 34.
What is a temperature and rainfall graph ?
Answer:
Temperature and rainfall graph is a type of composite thematic map, where the average monthly temperature is represented by the line graph and the total monthly rainfall is represented by bar graphs on the same graph paper. It helps to compare and analyse the temperature and rainfall conditions of a place at the same time.

Answer in brief : 3 Marks

Question 1.
What is the importances of water vapour in the atmosphere?
Answer:
The importances of water vapour in the atmosphere are –

1. Water vapour absorbs some insolation as well as back radiation of earth’s heat. Thus, it reduces atmospheric temperature to a certain extent.
2. It releases latent heat while condensation and may increase temperature to a certain extent.
3. Without water vapour, precipitation of no kind would have been possible (rain, snow, dew, fog etc.)
4. Too much presence of water vapour makes the atmospheric condition very humid and uneasy.
5. It influences growing of certain industries like cement, jute and flour.

Question 2.
Compare between Absolute Humidity and Relative humidity.
Answer:

Absolute Humidity	Relative Humidity
i. Represents the total or absolute amount of water vapour present in the unit volume of air at that particular temperature.	i. Represents the ratio between the present amount of water vapour and the total amount of water vapour that the unit volume of air can hold at that particular temperature.
ii. It is an absolute amount.	ii. It is a ratio.
iii. It is expressed in ‘grams’.	iii. It is expressed in percentage.
iv. It can remain constant throughout the day.	iv. It changes with change in atmospheric temperature in a day.
v. Does not give any idea whether rainfall may occur or not.	v. Gives an idea whether rainfall may occur or not.

Question 3.
How is rainfall measured ?
Answer:
Rainfall is measured with the help of an instrument called ‘Rain Gauge’. The rain gauge is planted till its half in the ground in an open space, where the rain water can directly fall into the instrument. This collected water is then poured into a measuring cylinder to record the amount of rainfall. It is expressed in millimetres or inches. Nowadays, a self-recording instrument called the ‘Hyetograph’ is used for measuring rainfall.

Question 4.
What is a rain-shadow area ?
Answer:
In maintainous areas, the moisture-laden clouds hit with the windward slope and shed the rains over there. The opposite or leeward slope of the mountain does not receive much or any rainfall. This drier slope of the mountain is called the rain-shadow area.

Question 5.
List the major climates of the world and their average annual temperature and rainfall conditions.
Answer:

Climate	Average annual temperature	250 cm
i. Wet equatorial climate	25°-27° C	100-150 cm
ii. Tropical Monsoon climate	25° C	below  16 cm
iii. Hot desert climate	30°-35° C	35-75 cm
iv. Mediterranean climate	13°-18° C	25-50 cm
v. Steppe Climate	16°-20° C	100-150 cm
vi. China Climate	27° C in summer 4° C in winter	250 cm (West)
vii. West coast Oceanic climate	16° C in summer, 4° C in winter	75 cm (East)
viii. West continental climate	20°-25° C in summer Below 0° C in winter	50-100 cm
ix. Wet temperate climate	10° C in summer Below 0° C in winter	25-50 cm
x. Tundra climate	-12° C	10-40 cm

Question 6.
What are the controlling factors of relative humidity?
Answer:
The controlling factors of relative humidity are –

1. Temperature – Temperature is inversely related to relative humidity. If temperature increases, water holding capacity of air increases, hence humidity decreases.
2. Water vapour – Increase in amount of water vapour in the air increases relative humidity.
3. Rainfall – Increase in rainfall is the result of increase in relative humidity.
4. Air pressure – Relative humidity is usually higher in regions of low pressure.

Answer in details : 5 Marks

Question 1.
Discuss the Convectional rainfall.
Answer:

Rainfall which is caused due to convectional currents in the atmosphere is called convectional rainfall. Excessive heating causes too much evaporation. Thus air is filled with water vapour. This heated and light air rises upwards until temperature reduces and reaches its dew point. The water vapour then condenses and forms

cumulus clouds. They further develop into cumulo-nimbus clouds at about 11 \mathrm{km} height. These clouds are very heavy and bring about rainfall, usually accompanied by thunder and lighting. These are also called Thunder showers. Convectional rainfall is most common in the Equatorial region, where it occurs almost daily in the afternoon around 4 o’clock. Hence, they are also called the 4 o’clock rains.

Question 2.
Discuss the occurrence of Orographic or Relief rainfall.
Answer:
When the moisture-laden winds blowing from sea strike against mountains, the humid winds rise up along the windward slope. As they rise, they cool down and bring heavy rainfall to the windward slope. Such a rain by uprising winds striking against mountains is called orographic (‘oro’- greek word meaning mountain) or Relief rainfall. Eg : Rainfall occuring on the southern slopes of the Himalayas.

Question 3.
Discuss the occurrence of cyclonic or frontal rainfall.
Answer:
The rainfall associated with the passage of a cyclone or depression is known as Cyclonic rainfall. It is formed where a warm air mass overrides a cold air along a front. When the warm and cold air masses move towards each other, the

warm air being lighter ascends over the cold air along the front. This leads to cooling the air, condensation and rainfall. Cyclonic rainfall occuring in Tropical regions is heavy and intense. Rainfall associated with Temperate cyclones is much lighter and less intense.

Detailed explanations in West Bengal Board Class 10 Geography Book Solutions Chapter 2.4 Pressure Belts and Winds offer valuable context and analysis.

WBBSE Class 10 Geography Chapter 2.4 Question Answer – Pressure Belts and Winds

Answer in short : 2 Marks

Question 1.
What do you mean by air pressure?
Answer:
The pressure exerted by the column of air of the atmosphere lying above a unit area of the earth’s surface is called air pressure.

Question 2.
What is an altimeter?
Answer:
Altimeter is an instrument for measuring altitude. It also measures air pressure along with altitude. It is commonly used by pilots, mountaineers etc.

Question 3.
What is a Fortin’s Barometer?
Answer:

Fortin’s Barometer is an instrument most commonly used for measuring atmospheric pressure. It is provided with a main scale and a vernier scale to measure air pressure with most accuracy.

Question 4.
What is an isobar?
Answer:
Isobars are imaginary lines drawn on weather maps joining places having same air pressure at a particular time of the year, considering the places to be at the mean sea level.

Question 5.
What is pressure gradient?
Answer:
The slope between the physical distance of two places and their pressure differences is known as the pressure gradient.

Question 6.
What are pressure belts ?
Answer:
The zones of the earth which exhibit similar pressure conditions on an average in circular belts according to the latitudes are called pressure belts. They can be either high pressure belts or low pressure belts.

Question 7.
What are pressure troughs?
Answer:
Although the entire earth is divided into pressure zones, some areas may exhibit a little different pressure conditions than their surroundings. These areas may be enclosed with certain isobars. Such circular zones of pressure conditions are called pressure troughs.

Question 8.
Mention the factors on which difference of air pressure depends.
Answer:
The air pressure conditions depend on the following factors :

1. Temperature of the wind.
2. Altitude of the place.
3. Amount of water vapour in the air.
4. Rotation of the earth.
5. Depth or height of the air column above the place.
6. Distribution of land surface and water bodies etc.

Question 9.
What is wind and air current?
Answer:
The horizontal movement of the air from high pressure regions to low pressure regions is known as wind. The vertical movement of air above the earth’s surface is known as air current.

Question 10.
State Ferrel’s law.
Answer:
Ferrel’s law states that due to the coriolis force created by the rotation of the earth, the winds are deflected towards the right in the northern hemisphere and towards the left in the southern hemisphere.

Question 11.
What is a Beufort scale?
Answer:
Beufort scale is a scale designed by Sir Francis Beufort, to measure the energy of wind. It is marked from 0-12. ‘0’ refers to a calm state of wind and ’12’ refers to a highly destructive and ferocious tornado.

Question 12.
What are roaring forties ?
Answer:
The roaring forties are extremely powerful westerly winds that blow in the southern hemisphere between latitudes 40°-50°. These gale-force, west to east currents are the result of the combination of three variables : warm air movements, the earth’s rotation and near absence of relevant landmasses in southern hemisphere.

Question 13.
What is Loo?
Answer:
The ‘Loo’ is a strong, dusty, hot and dry summer wind from the west which blows over the Indo-Gangetic plain of North India and Pakistan. It is mainly blows in Summer (May to June). Due to its very high temparature, exposure to it often leads to total heat strokes.

Question 14.
What is Buys Ballot’s law ?
Answer:
In the Northern Hemisphere, if a person stands with his back to the wind the atmospheric pressure is low to the left, high to the right. This is because, wind travels anticlockwise around low pressure belt in the Northern Hemisphere, and is reversed in the Southern Hemisphere.

Question 15.
What is Geostrophic wind ?
Answer:
In the condition of Geostrophic equilibrium, a thin wind stream is generating when pressure gradient force and coriolis force come into exact balance. It is a upper layer atmospheric wind.

Question 16.
What is an anemometer?
Answer:
Anemometer is an instrument used to measure wind speed.

Question 17.
What are planetary winds?
Answer:
The earth has certain fixed high pressure and low pressure belts that lie paralle] to the equator. This generates winds blowing from high to low pressure regions in fixed directions throughout the earth. These winds that blow regularly in specific directions throughout the year are called planetary winds.

Question 18.
What are trade winds?
Answer:
Winds that blow from the subtropical hight pressure belts or horse latitudes (30°-35° north and south) to the low pressure belts or doldrums (5°N-5°S) are known as the Trade winds.

Question 19.
Why are trade winds so called ?
Answer:
Trade winds blow over the region of the earth which has much landforms and large population. In early days, the sailors used to sail their ships with the help of the trade winds for trade and business from one continent to another. Hence the winds are called ‘Trade winds’.

Question 20.
What are westerlies?
Answer:
The winds that blow from sub-tropical high pressure belts towards the sub-polar low pressure belts are called westerlies. They blow towards the poles generally from south-west in the northern hemisphere and from the north-west in the southem hemisphere. As they blow from the west in both the hemispheres, they are called westerlies.

Question 21.
What are polar winds?
Answer:
The winds that blow from the high pressure region of poles towards the sub-polar low pressure zones are called polar winds. Since they blow from the east in both the hemispheres, they are also called Polar Easterlies.

Question 22.
What are periodic winds ?
Answer:
Some winds that blow for a limited period of a day or time to time or for a certain season of the year are called periodic winds. Eg. – sea breeze, land breeze, monsoon winds etc.

Question 23.
What is sea breeze?
Answer:
During day time, the wind that blows from sea towards the land is known as sea breeze. This happens due to unequal heating of land and sea and difference in pressure conditions thus created.

Question 24.
What is land breeze?
Answer:
During the night, the wind that blows from land towards the sea is called land breeze. This is because of the unequal rates of radiating heat by land and sea after sunset, hence creating a difference in pressure conditions over the land and sea surfaces.

Question 25.
What are local winds ?
Answer:
There are certain type of winds which are produced by local temperature differences created due to local topographic landform. These winds are called local winds, and their zone of influence is also very small. Eg. – Sirocco, Loo etc.

Question 26.
What are sudden or irregular winds ?
Answer:
Intense heating or cooling of land and sea sometimes develop severe low pressure centre or centre of high pressure. It brings about irregular winds of great or mild speed. These are called sudden or irregular winds. They do not have any routine time of occurrence.

Question 27.
What is a cyclone?
Answer:

Cyclones are stormy whirls of wind. They come suddenly with great force and velocity towards the centre of low pressure. Cyclone develops due to the formation of intense low pressure centre. As it approaches, it spins clockwise in the southern hemisphere and anti-clockwise in the northern hemisphere.

Question 28.
What is a Jet stream ?
Answer:

Jet stream is a thin stream of air generated in the higher reaches of the Troposphere and below the Stratosphere at about 7.4-14 km. altitude. It blows from west to east. Length of this jet stream can be a few thousand kilometer, but the width is only a few hundred kilometre.

Question 29.
What do you mean by ‘Roaring Forties’?
Answer:
In the southern hemisphere, sea surface is much more compared to land surface. Hence, the westerlies can blow over this zone unhindered and with great speed near the 40° S latitude. The wind blows with so much speed that it makes a roaring sound. Hence, the region is called ‘Roaring Forties’.

Question 30.
What are Anabatic wind?
Answer:
Anabatic winds are also called up-slope winds. In mountainous regions, during the day, when the solar radiation heats the mountain slopes, the adjacent cool air gets heated, lightened and rises upward. These are called Anabatic wind.

Question 31.
What are Katabatic winds ?
Answer:
Katabatic winds are also called down-slope winds. In mountainous regions, during the night, when the slopes cool down due to outgoing solar radiation, the adjacent air also cools, gets heavier and sinks down the slopes into the valleys.

Question 32.
What is Sirocco?
Answer:
It is a very hot dry wind of the Sahara desert. It blows from Sahara to the Mediterranean region. It is known as Khamsin in Egypt, Harmattan in Guinea coast of West Africa and Sirocco in Sicily.

Question 33.
What is Mistral ?
Answer:
Mistral is a strong, cold northernly wind experienced on the shores of the northwest Mediterranean region. It blows along the coasts of Spain and France.

Question 34.
What is Bora?
Answer:
Bora is a cold dry wind that blows along the adriatic coast and in northern Italy during winter.

Question 35.
How many kinds of air pressure are there?
Answer:
There are two kinds of air pressure :
(i) High pressure : When air pressure is higher than 760 mm of mercury or 986 millibar.
(ii) Low pressure : When air pressure is lower than 760 mm of mercury or 986 millibar.

Question 36.
What do you mean by Standard Atmospheric Pressure?
Answer:
The pressure exerted by 76 cm of mercury in a bore tube at 0° C temperature on 45° latitude at sea level is known as Standard Atmospheric Pressure.

Question 37.
What kind of pressure is considered as normal air pressure ?
Answer:
Air pressure lying between 986-1013.25 millibars is considered as normal air pressure.

Question 38.
What happens if the isobars lie very close to each other?
Answer:
The closely lying isobars indicate a steep pressure gradient. Steep pressure gradients initiate strong and speedy winds. It increases the chances of storms and cyclones.

Question 39.
Is the atmospheric pressure at sea level all over the world same?
Answer:
It has been tested that atmospheric pressure at sea level does not rise above 788 mm and does not fall below 760 mm. But atmospheric pressure at sea level all over the world is not absolutely same. It varies due to temperature conditions of adjacent areas.

Question 40.
What is the difference between Trough and Ridge?
Answer:
A huge region of low pressure is known as Trough and a huge region of high pressure is known as Ridge.

Question 41.
What kind of pressure conditions prevail over the earth in January?
Answer:
In January, low pressure prevails over the southern hemisphere and high pressure prevails over the northem hemisphere.

Question 42.
What kind of pressure conditions prevail over the earth in July?
Answer:
In July, high pressure prevails over the southern hemisphere and low pressure prevails over the southern hemisphere.

Question 43.
What is the Normal lapse rate of air pressure ?
Answer:
With every 110 m rise in altitude, the atmospheric pressure decreases by 1 cm or 10 mm of mercury in the Barometer, or by 1.34 millibar. This is the normal lapse rate of air pressure.

Question 44.
What is ‘Knot’?
Answer:
‘Knot’ is the unit of measuring winds speed. Knot means the distance in nautical miles, travelled in one hour.

Question 45.
What is an anti-cyclone?

Air pressure increases with decrease in air temperature. When this condition gets intensified, the isobars lie in circular patterns with a high pressure in the centre and low pressure towards the periphery. Thus, winds start blowing outwards from the centre in clockwise direction in the northern hemisphere and in anti-clockwise direction in the southern hemisphere.

Question 46.
Name two local winds in India.
Answer:
Two local winds in India are Loo and Andhi.

Answer in brief : 3 Marks

Question 1.
Mention the characteristics of air pressure.
Answer:
The characteristics of air pressure are :

1. Air pressure decreases with increase in altitude.
2. Hot air is lighter and exerts less pressure.
3. Cold air is heavier and exerts more pressure.
4. Water vapour makes the concentration of gaseous molecules in the air lighter, and hence exerts less pressure. Thus, dry air exerts more pressure than moist air.
5. Sudden change in pressure conditions result in severe storms.
6. Air exerts pressure on all directions.
7. Air pressure is measured in millibar.

Question 2.
Compare between high pressure and low pressure.
Answer:

High Pressure	Low Pressure
i. When air exerts much pressure, it is called high pressure.	i. When air exerts less pressure, it is called low pressure.
ii. Length of mercury column in the glass tube of the barometer is more than 760 mm or 1013.25 millibar.	ii. Length of mercury column in the glass tube of the barometer is less than 760 mm or 1013.25 millibar.
iii. The high pressure zones of the earth are sub tropical high pressure zones near the Tropics of Cancer and Capricorn, and polar hight pressure zones near the North pole and the South pole.	iii. The low pressure zones of the earth are Equatorial low pressure zone, sub polar low pressure zones near the Arctic and Antarctic circles.

Question 3.
Why do high pressure zones lie near the polar areas?
Answer:
High pressure belts lie around the polar regions because,

1. The sun gives the most inclined rays to this region. Heat is very less, hence the air is very cold and heavy.
2. There is very less water vapour in the air as the rate of evaporation is very low.
3. Some air from the adjacent sub-polar low pressure belts rise and descend towards the poles.

Question 4.
Why is the equatorial region a low pressure belt ?
Answer:
The equatorial region has a low pressure belt because:

1. The sun gives its maximum energy to this region by rays perpendicular to the surface. Hence, heat is maximum. The air gets heated, lightened and rises up.
2. Presence of huge water bodies and much heat leads to high rates of evaporation. The air is filled with water vapour and becomes light.
3. The rotation of the earth tends to deflect air due to coriolis force.
4. Presence of vast forests adds up to water vapour in the air due to transpiration.

Question 5.
What are horse latitudes?
Answer:
The sub-tropical belt of calm lying between 25°-35° N is known as Horse latitudes. In early days when trade was conducted only through the oceans, the ships used to slow down and could not sail through this region due to lack of wind. Then in order to reduce weight and preserve drinking water, the horses being carried in the ships were thrown into the ocean. Thus the region was named horse latitudes.

Question 6.
What do you mean by ‘Shifting of Pressure belts’?
Answer:
The rotation of the earth, angle of incidence of solar rays, presence of land surface or water surface, altitude and the seasonal drift of the sun towards the north and towards the south cause the pressure belt to shift by 5°-10° northwards and southwards respectively. This temporary movement of the pressure belts makes them move for about 5°-10° from their average positions. This phenomena is known as ‘shifting of pressure belts.’

Question 7.
Differentiate between wind system and wind current.
Answer:

Wind system	Wind current
i. Wind moves horizontally parallel to the earth’s surface.	i. Wind moves vertically perpendicular to the earth’s surface.
ii. Occurs due to difference in pressure between two places.	ii. Occurs due to difference in temperature.
iii. Influence on human life is remarkable.	iii. Influence on human life is negligible.

Question 8.
Differentiate between north-eastern trade winds and south-eastern trade winds.
Answer:

North-eastern Trade winds	South-eastern Trade winds
i. Blows between 5°-25° N latitudes.	i. Blows between 5°-25° S latitudes.
ii. The wind blows from the region around the Tropic of Cancer towards the Equator.	ii. The wind blows from the region around the Tropic of Capricorn towards the Equator.
iii. Wind gets deflected towards the right.	iii. Wind gets deflected towards the left.
iv. Wind speed is comparatively low due to presence of more land surface in the northern hemisphere. (about 16 km per hour)	iv. Wind speed is high due to presence of vast oceanic surface and less land surface in the southern hemisphere. (about 22 km per hour)

Question 9.
List the characteristics of Westerlies.
Answer:
The characteristics of Westerlies are :

1. Westerlies bring rainfall to western margins of continents.
2. The continents under the influence of westerlies have temperate grasslands on their eastern sides.
3. Westerlies bring about more rainfall during the winter.
4. In the southern hemisphere, the westerlies blow with great speed due to vast ocean surfaces unhindered by land. Hence, the latitudes are named – Roaring Forties, Furious Fifties and Screaming Sixties.

Question 10.
What is an Anticyclone?

Answer:
Winds generated in a region of high pressure surrounded by low pressure all around is called an Anticyclone. In this system, the winds blow spirally outwards from the centre in clockwise direction in the northern hemisphere and anticlockwise direction in the southern hemisphere. Anticyclones are generally associated with light wind and clear sky. Rainfall is light or in drizzles. They prevail commonly in winter when cold air remains near the ground for many years.

Question 11.
Differentiate between land and sea breezes and monsoon winds.
Answer:

Land and Sea breezes	Monsoon winds
i. Blows near coastal areas.	i. Generates near oceans and blows towards land for a long distance in tropical region.
ii. Land and Sea breeze blows alternately for few hours. Land breeze blows during the night and sea breeze blows during the day.	ii. Blows for a few months in a particular season. During summer the wind blows from sea to land, during winter they blow from land to sea.

Question 12.
Differentiate between cyclones and anti-cyclones.
Answer:

Cyclone	Anti-cyclone
i. Low pressure lies in the centre of a cyclone.	i. High pressure lies in the centre of an anti-cyclone.
ii. Winds blow towards the centre.	ii. Winds blow outwards from the centre.
iii. Winds are warm and move upward.	iii. Winds are cold and move downward.
iv. Winds blow anti-clockwise in the northern hemisphere and clockwise in the southern hemisphere.	iv. Winds blow clockwise in the northerm hemisphere and anti-clockwise in the southern hemisphere.
v. Wind velocity is very high.	v. Wind velocity is low.
vi. Cause storms and rainfall.	vi Usually cause no rainfall.
vii. Exists for a short time, but is destructive.	vii. Exists for a long time but is not destructive.

Question 13.
Compare the atmospheric pressure conditions of January and July.
Answer:

Pressure conditions in January	Pressure conditions in July
i. High pressure lies in northern hemisphere and low pressure lies in southern hemisphere.	i. High pressure lies in southern hemisphere and low pressure lies in northern hemisphere.
ii. The pressure belts shift southwards with the southward movement of the sun.	ii. The pressure belts shift northward with the northward movement of the sun.
iii. During this time the wind blows from land towards the sea in the northern hemisphere.	iii. During this time, the wind blows from land towards the sea in the southern hemisphere.

Question 14.
Discuss the effects of air pressure.
Answer:
The effects of air pressure are –

1. Difference in air pressure of different parts of the earth’s surface is the main cause of wind.
2. Heavy storms and often rainfall occur in regions of very less pressure.
3. Snowfall occurs in high pressure regions.
4. Air pressure influences wind, heat and presence and holding capacity of water vapour by the air.
5. Higher altitudes have low pressure. Hence, mountaineers have to carry oxygen cylinders for breathing.
6. In higher altitudes, due to sudden decrease in atmospheric pressure, bleeding may start from nose, ears, eyes etc.

Question 15.
Discuss the characteristics of winds.
Answer:
The horizontal movement of air along the earth’s surface from a region of high pressure to a region of low pressure is known as wind. The characteristics of winds are –

1. Winds blow from high pressure to low pressure regions.
2. Winds (especially planetary winds) are named according to the directions from where they blow.
3. Wind speed depends on the pressure gradient between two places.
4. Wind direction is marked by a Wind Vane.
5. Wind speed is measured by Anemometer in ‘Knots’.
6. The force of the wind is calculated on the Beufort Scale.

Question 16.
What is ‘Coriolis Force’?
Answer:
‘Coriolis Force’ is generated due to the rotation of the earth. The earth being a sphere, speed of rotation goes on reducing from the equator towards the poles. The moving elements on the earth’s surface (wind, ocean currents) thus cannot flow directly in the north-south direction, and get slightly deflected. This was first discovered by the French physicist and mathematician G.G. Coriolis in 1835. Thus the force that causes deflection of moving bodies on the earth’s surface due to rotation is called the ‘Coriolis Force’. In the northern hemisphere, the winds get deflected towards the right and in the southern hemisphere, the winds get deflected towards the left.

Question 17.
Differentiate between the South-West Westerlies and the North-West Westerlies.
Answer:

South-West Westerlies	North-West Westerlies
i. They blow from the Tropic of Cancer towards the Arctic Circle in the northern hemisphere.	i. They blow from the Tropic of Capricorn towards the Antarctic Circle in the southern hemisphere.
ii. They blow between \(23^{1 / 2}\)° N \(66^{1 / 2}\)°N.	ii. They blow between \(23^{1 / 2}\)°S \(66^{1 / 2}\)°S.
iii. Wind speed is lesser than the NW westerlies.	iii. Wind speed is greater than the SW westerlies.
iv. Horse Latitudes lie within this zone.	iv. Roaring 40s lie within this zone.

Question 18.
Why do westerlies cause more rainfall on the western coasts of the continents?
Answer:
The causes of rainfall on the western coasts of the continents by Westerlies are:
i. Westerlies blow from the west towards the east. Hence, before they enter the continent from the western side, they blow over oceans and collect enough moisture.
ii. The continents under the influence of westerlies have mountains and high lands along the western margins. This helps to stop the moisture laden winds and cause rainfall.

Question 19.
Why do the eastern parts of the continents under the influence of westerlies receive less rainfall ?
Answer:
The eastern parts of the continents under the influence of Westerlies receive less rainfall because –
i. The Westerly winds become more and more dry as they move from west to east over the continents and cannot collect moisture due to lack of water bodies.
ii. They shed maximum water at the western margins of the continents due to collision with highlands and mountains.

Question 20.
Differentiate between Trade winds and Westerlies.
Answer:

Trade winds	Westerlies
i. Blow from the Tropic of Cancer and Capricorn towards the Equator.	i. Blow from the Tropic of Cancer to the Arctic Circle and Tropic of Capricorn to the Antarctic Circle.
ii. Blow from the east towards the west.	ii. Blow from the west towards the east.
iii. Wind speed is 16 km per hour in the northern hemisphere and 22 km per hour in the southern hemisphere.	iii. Wind speed is low in the northern hemisphere due to presence of landmass. Wind speed is high in the southern hemisphere due to presence of oceans.
iv. Helped in sailing of ships in early days.	iv. Cause danger to ships sailing in the southern hemisphere due to great wind speed.
v. Cause rainfall on the eastern side of continents.	v. Cause rainfall on the western side of continents.
vi. Cause uniform rainfall in the equatorial region throughout the year.	vi. Cause more rainfall in the winter compared to the summer.

Question 21.
Differentiate between Sea Breeze and Land Breeze.
Answer:

Sea Breeze	Land Breeze
i. Blows during day time from the sea towards the land.	i. Blows during night from the land towards the sea.
ii. Wind speed is greater than land breeze.	ii. Wind speed is lesser than sea breeze.
iii. Wind speed is greatest during noon.	iii. Wind speed is greatest during early morning.
iv. Winds cover a larger area while blowing.	iv. Winds cover a lesser area while blowing.

Question 22.
What is a Cyclone?
Answer:

If a small area suddenly gets heated up, the air present over that area also get heated, lightened and rise upwards. This creates a low pressure trough in the area compared to the surrounding areas. Thus, winds gush in with great speed from all sides towards the centre of low pressure. This is known as a Cyclone. The cyclonic winds move in circular patterns. They blow in the anti-clockwise direction in the northern hemisphere and clockwise direction in the southern hemisphere.

Answer in details : 5 Marks

Question 1.
Discuss the factors affecting atmosphere pressure.
Answer:
The factors that affect atmospheric pressure are :
i. Temperature : Air pressure is inversely related to temperature. Higher the temperature, lower is the air pressure. As air gets heated, it gets lighter and rises upwards, thus exerts less pressure. Conversely, cold air contracts, becomes heavier and descends, thus exerts more pressure.

ii. Altitude : Atmospheric pressure is inversely related to altitude. The lower layers of the air are denser than upper layers. Moreover, the lower layers are compressed
under the weight of the upper layers of air and exert more pressure. As we go higher up, pressure decreases by 10 mm per 110 m rise in altitude.

iii. Water vapour : Air containing water vapour is lighter than dry air. Thus moist air exerts less pressure than dry air.

iv. Rotation of the earth : Rotation of the earth results in swing of air outwards due to centrifugal force. Thus regions of the earth rotating with the highest speed have low pressure zone.

v. Distribution of land and water : Pressure conditions on land and water on the same latitude are not the same. During summer, the land gets heated more than the water, thus a low pressure region is created on the land. The opposite condition occurs in winter.

Question 2.
Discuss the Pressure belts of the world in brief.
Answer:
The world is divided into seven distinct pressure belts. They are :
(i) The Equatorial low pressure belt
(ii) and (iii) The sub-tropical high pressure belts (North and South)
(iv) and (v) The sub-polar low pressure belts (North and South)
(vi) and (vii) The Polar high pressure belts (North and South)

(i) Equatorial low pressure belt : This belt lies between 5°N and 5°S of the Equator. The earth receives maximum heat here. Hence the air is always hot and light. The air also contains a large amount of water vapour. This light air rises vertically giving, rise to a low pressure belt. The region is generally windless and calm. Hence it is also known as doldrums.

(ii) and (iii) The Sub-tropical high pressure belts : These belts extend between 30°-35° N and S. These high pressure belts are not thermally induced. They result due to rotation of the earth, sinking, settling down and piling of air from the equator and sub-polar regions. The cool descending air gradually becomes warm and its water holding capacity increases. As a result there is no condensation and occurrence of rainfall. This is one of the reasons for occurrence of hot deserts on the western sides of the continents present in this region.

(iv) and (v) The Sub-polar low pressure belts : These belts lie between 60°-65° N and S. Due to earth’s rotation, the surface air spreads outward, causing creation of low pressure. The belt is more developed in the southern hemisphere compared to the northern hemisphere because of the presence and dominance of water (oceans) in the southern hemisphere in this belt.

(vi) and (vii) the Polar high pressure belts : These belts lie around the poles in both the hemispheres. These regions have permanent ice caps. Due to immense cold and minimum speed of rotation, the air which is cold and dense, descends near the poles, creating high pressure.

Question 3.
Discuss the causes of wind movement over the earth’s surface.
Answer:
The different causes for wind movement over the earth’s surface are –
i. Difference in temperature : If a place gets heated, the air lying above it also gets heated and lightened and rises up creating a partial vacuum. Thus air rushes from adjacent cooler airs to fill up the vacuum.
ii. Difference in pressure : Difference in temperature between two places cause difference in pressure. Thus winds blow from high pressure to low pressure regions.
iii. Rotation of the earth : While blowing from high pressure to low pressure regions, winds get deflected due to the rotation of the earth.
iv. Nature of landforms : High mountains or plateaus provide obstruction to the wind, hence speed is less. But vaccant and flat places like deserts, plains, etc. experience very speedy winds.
v. Presence of land or water surface: Winds blowing over land surface experience more friction than winds blowing over water surface. Hence wind blowing over land have less speed than wind blowing over water.

Question 4.
Discuss the charateristics of Planetary wind in brief.
Answer:
There are three types of planetary wind:

1. The Trade winds
2. The Westerlies
3. The Polar winds.

i. The Trade winds : Winds that blow from the Sub-tropical high pressure belts to the Equatorial low pressure belts are called Trade winds. According to Ferrel’s

law, due to Coriolis force, caused by earth’s rotation winds deflect to the right in the northern hemisphere and to the left in the southern hemisphere. Hence, the winds are called north-east trade winds in the northern hemisphere and the south-east trade winds in the southern hemisphere. Velocity of NE trade winds is around 16 km per hour and that of SE trade winds is 22 km per hour (due to less landforms and vast oceans).

ii. The Westerlies : The winds blowing from the sub-tropical high pressure belts to the sub-polar low pressure belts are called Westerlies. As the direction of the Westerlies is opposite to that of trade winds, they are also called Anti-trade winds. In the northern hemisphere they blow from the south-west and in the southern hemisphere they blow from the North-West.

iii. The polar winds : The chilled winds blowing from the polar regions to the subpolar low pressure regions are called the polar winds. Since their direction is similar to that of Trade winds, they are also called Polar Easterlies or Polar Trade winds. In this region, the deflection of winds is so high that they appear to blow almost from the east.

Question 5.
What is the ‘Jet Stream’? Discuss its relation with the monsoon winds.
Answer:

Jet stream is a thin stream of air generated in the higher reaches of the Troposphere and below the Stratosphere at about 7.5-14 km. altitude. It blows from west to east. The jet stream can be a few thousand kilometer but width is only a few hundred kilometer.

Relation between Jet stream and Monsoon winds : The westerly Jet stream causes high pressure on the Indian subcontinent in winter. Hence the summer, the Tibet plateau gets excessively heated and drives the subtropical westerly Jet stream north of the Himalaya. The tropical easterly jet stream blows through the centre of the Indian sub-continent, causing low pressure conditions. This gradually attracts the monsoon winds. The onset of monsoon depends on the shifting of the sub-tropical westerly jet stream northwards, which allows the easterly jet to set in. A sudden shift of the westerly jet stream may cause a huge ‘Monsoon burst’.

Question 6.
Differentiate between cyclones and anti-cyclones.
Answer:

Question 7.
Describe some local winds of the earth.
Answer :
i. Sirocco or Khamsin : It is a very hot dry wind of the Sahara desert. It blows from Sahara to the Mediterranean region. It is known as Khamsin in Egypt, Harmattan in Guinea coast of West Africa and Sirocco in Sicily.
ii. Mistral : It is a strong, cold northernly wind experienced on the shores of the North-West Mediterranean region. It blows along the coasts of Spain and France.
iii Bora : It is a cold and dry wind that blows along the Adriatic coast and in northern Italy during winter.
iv. Fohn : It is a warm dry wind blowing down the northern slope of the Alps. Initially it rises as a moist wind from the Mediterranean sea.
v. Chinook : It is a warm, dry, gusty wind blowing down the Rocky mountains by the eastern slopes into the western Prairies.
vi. Loo : It is a strong, dry, hot summer afternoon wind blowing over-North Western India and Pakistan, especially in May and June.
vii. Others : Pampero, Blizzard, Santa Ana, Norwesters etc.