Practicing with West Bengal Board Class 10 Geography Book Solutions and West Bengal Board Class 10 Geography Question Paper 2019 alongside detailed explanations can lead to a deeper understanding of the subject.

WBBSE Class 10 Geography Question Paper 2019

Group-A

1. Write the correct answer from the given alternatives

1. The process by which the height of the earth’s surface increases is ………….
Answer: Aggradation.

2. Deep cracks on the surface of the mountain glacier are called ………….
Answer: Crevasse.

3. Annual range of temperature remains minimum in ………….
Answer: Equatorial climate region.

4. Cold local wind that blows in Rhone valley of France is called ………….
Answer: Mistral

5. The place where warm and cold ocean currents converge is called ………….
Answer: Cold wall.

6. When the distance between the earth and the moon is farthest, it is called-
Answer: Apogee.

7. In human body, contaminated water may cause ………….
Answer: Diarrhoea.

8. The main basis of state recognisation in India is ………….
Answer: Language.

9. The source of river Ganga is ………….
Answer: Gangotri glacier.

10. In India, the largest multipurpose river valley project is ………….
Answer: Bhakra-Nangal.

11. The state which ranks first in production of rice per hectare is ………….
Answer: West Bengal.

12. The required raw materials of iron and steel industry include.
Answer: All of them.

13. According to 2011 census the number of metropolis in india is ………….
Answer: 53

14. The latitudinal and longitudinal extension of million sheet topographical map is ………….
Answer: 4°x4°

Group-B.

1. If the statement is true, write ‘T’ and if false, write ‘F’ against the following :

1. Altitude of snowline varies with latitudes.
Answer: True

2. Wind velocity is measured with the help of Anemometer.
Answer: True

3. Salinity of sea-water is maximum in Equatorial region.
Answer: False

4. The highest plateau of India is Deccan Trap.
Answer: False

5. The old alluvial soil of Ganga plain is called Bhangar.
Answer: True

6. Vishakhapattanam is the only tax-free port of India.
Answer: False

7. Red coloured lines are used to show roads in satellite images.
Answer: False

2. Fill in the blanks with suitable words

1. Holes formed by abrasion on river bed are called pot holes.
2. Smog is formed by mixing of dust and fog during winter in industrial region.
3. Labrador current causes snowfall in New Foundland.
4. Waste paper is a solid/biodegradable type of wastes.
5. Tropical early jetstream forests south-west monsoon winds to blow over India.
6. The southernmost most paint of mainland India is kanyakumari.
7. Kolkata is the most populous city of India.

3. Answer in one or two words

1. Which type of rainfall is found in Temperate zone?
Answer: Frontal or cyclonic rainfall.

2. Which island of Sundarban was completely submerged due to global warming?
Answer: New Moore island.

3. Which type of natural vegetation is found in the desert region of India?
Answer: Xerophytes.

4. On which quarters of moon, does Neaptide occur?
Answer: 1st and 3rd quarters of the moon.

5. In which part of the course, river Ganga is maximum polluted?
Answer: Middle course.

6. Name one Zaid crop of India.
Answer: Aus rice, nuts, pumpkin, cucumber, etc.

7. Which state of India leads in ‘Rain-water harvesting’?
Answer: Tamil Nadu.

8. Where is the headuarter of ‘Survey of India’ located?
Answer: Dehradun.

4. Match the left column with the right column.

1. Prominence of ozone gas	a. Gurgaon
2. Research Institute of sugarcane	b. Jammu & Kashmir
3. Largest automobile manufacturing industrial centre	c. Stratosphere
4. Karewa	d. Lucknow

Answer:
1- c, 2-d, 3-a, 4-b

Group-C

3. Answer the following in brief

Question 1.
What is denudation?
Answer:
After weathring, when the weathered earth materials are remained from their position by erosion and mass wasting, the surface beneath the debris becomes open and forms a new landform. This process of opening up of the new surface of the landform is called denudation.
Denudation-Weathering + Erosion + Mass wasting

OR.

What is inversion of temperature?
Answer:
By the normal lapse rate, temperature reduces by 6.4°C with every 1km or 1000m rise in altitude. But in some cases, it is seen that temperature increases with increase in height or altitude. This phenomenon is known as the inversion of temperature. This is common in valleys of mountainous regions during early morning and late night

Question 2.
What is ‘Inter-tropical convergence zone’?
Answer:
The Inter-tropical convergence zone is the region around the equator, extending up to about 5°-10° N and S latitudes. It is called so because the Northeastern and South-eastern Trade winds meet in this region.

OR.

State the definition of ocean current.
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. they are mostly caused by wind direction, rotation of the earth, temperature, salinity and density of ocean water, prsence and location of landmass, etc. Ocean currents are of two types-warm currents and cold currents.

Question 3.
Define waste management.
Answer:
Waste management is the method of collecting wastes scientifically, segregating then, taking steps for recycle, reuse and reduction, so that the ultimate damage or pollution caused by the wastes comes down to the minimum.

OR

What do you mean by radioactive wastes?
Answer:
Radioactive wastes are by-products of various nuclear technology processes. Industries generating radioactive wastes include nuclear medicine, nuclear research, nuclear power, manufacturing, construction, coal and rare-earth mining, nuclear weapons reprocessing, etc, Radioactive wastes include any material that is either intrinsically radioactive or that has been contaminated by radioactivity.

Question 4.
Where is Malnad region located?
Answer:
The Malnad region is located in the western part of the Karnataka plateau. This region is 320km long and 35km wide. It is highly dissected, and have deeply cut valleys.

OR.

Name two watershed regions of India.
Answer:
The main watershed regions of India are :

• The Himalaya and the Karakoram ranges.
• The Vindhya-Satpura ranges.
• The Western Ghats.

Question 5.
What do you mean by millet crops?
Answer:
Millets are a group of highly variable small-seeded grasses, widely grown in India as well as around the world as foodgrains for man and fodder for animals. The millets are hardy grains that can grow well in dry zones as rain-fed crops, under conditions of low soil fertility and low soil moisture. Eg- Jowar, Bajra, Ragi, etc.

OR.

Name one agro-based and one forest-based industries of India.
Answer:

• Agro-based industries in India: Sugar mills, rice mills, cotton textile industry, edible oil mills, tea industry, coffee industry.
• Forest-based industries in India: Paper industry, match box and card board industry, rubber industry, furniture industry.

Question 6.
State the definition of satellite imageries.
Answer:
Satellite imageries are photographs of the earth and other planets captured by imaging satellites that are installed in space. These are prepared by reading and representing the signals sent by the satellites with the help of high technological know-how.

OR.

State the use of Representative Fraction (R.F.)
Answer:
Representative Fraction (R.F) is a scale which is represented as a fraction that contains no unit. Hence, it can be used for any unit eg. cm to m or km, inch to feet, etc. It is readable and usable in any country with a unit system suitable to them.

Group-D

4. Give brief explanatory answers

Question 1.
State three differences between ‘Seif dunes’ and ‘Barkhans’
Answer:
Seif dunes

• The term Seif comes from the Arabian word ‘Seif’ meaning a straight sword.
• Formed like straight lines parallel to the wind direction
• They are narrow and straight and look like parallel ridges.
• They are very long dunes, Width is very less, but height may be a few be hundred metres.

Barkhans

• The term Barkhan comes from the Turkish word ‘Barkhan’ meaning sand mountain.
• Formed like a curve diagonal or perpendicular to wind direction.
• They are crescent-shaped dunes. The windward side is convex and the beward side is concave.
• They are not very huge in size. Widthh lies between 20-30m and height may around 30m.

OR.

Briefly explain any three factors to identify the mediterranean climate in Temperature-Rainfall graph.
Answer:
The Mediterranean climate can be identified with the help of the following factors :

• Average annual temperature remains about 13°- 18°c
• Average summer temperature is 14°-22°c
• Average winter temperature is 10°-14°c
• Average annual rainfall is 35-75cm, which mostly occurs during winter due to the moist westerly winds.

Question 2.
Briefly discuss any three effects of wastes on environment.
Answer:
The effects of wastes on the environment are :

• Solid wastes lying on the ground for a long time pollute the soil and water of the region. It may spread bad smell and cause air-pollution as well.
• Chemical wastes coming from pesticides, insecticides, etc. Tend to reduce nitrogen content of the soil and reduce fertility. Numerous animals and microorganisms may get killed, and land may gradualy become unproductive.
• Accumulation of wastes in rivers, lakes, ponds, oceans, etc. cause death of numerous aquatic plants and animals. Fishes may loose their reproductive capacity. Water ecosystems may get disrupted.
• Wastes disposed on grounds change the chemical properties of soils. Soils may become acidic and salty and unfit for vegetation growth.

OR.

Briefly discuss the role of students in waste management from any three perspectives.
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-

i. Reduce waste creation :

• Use towels and ceramic plates instead of paper napkins and disoposable plates.
• Use biodegradable shopping bags instead of plastic bags.

ii. Reuse things :

• Use old clothes, old toys, books, etc. from elders.
• Make innovative items from discarded things Eg- Penstand from soda cans, Rags from old clothes.

iii. Cleaning programmes :

• Awareness camps and demonstration programms regarding garbage disposal.
• Schools can arrange groups of students for regular survey, Whether the local people are following cleaning and garbage disposal systems or not.

Question 3.
Mention three differences about characteristic features of tropical evergreen and tropical deciduous vegetation of India.
Answer:

Tropical Evergreen forests	Tropical deciduous forest
i. Tropical evergreen forests are very dense.	i. Tropical deciduous forests are compartively less dense.
ii. The trees are very tall and highly branched.	ii. The trees are moderately tall and branched.
iii. The trees do not shed their leaves altogether in one season. Thus the forest appears green throughout the year.	iii. The trees shed their leaves together in the dry season, hence the name deciduous.
iv. The leaves of the trees create a canopy over the head of the forest and allow very little sunlight to penetrate the forest.	iv. The leaves of the trees are comparatively smaller in size, hence do not create a canopy over the head of the forest. Hence, the forests receives sufficient sunlight.

OR.

Explain with examples the influence of raw materials on the developments of industries in India.
Answer:
Development of industries in any region is dependent upon various factors. Raw materials is one of them.

a. Availability of a certain raw material in a region determines the development of a particular industry in that region. Eg-Availability of coal and iron are along with other necessary raw materials in the Asansol-Durgapur belt has helped in the growth of iron and steel industry in that region.

b. Unless the particular raw material is available in a particular region, the related industry cannot grow, even if all other necessary things are available. Eg-Sugar industry cannot develop in Rajasthan due to unavailability of sugarcane in the vicinity.

c. Nature of raw materials determines the location of the industry. Eg-Sugar mills must be located near the sugarcane producing regions, so that the canes can be moved to the mills very fast. If the raw materials are pure, like cotton industry can be located at the source of raw materials or at the market.

Question 4.
Briefly discuss about three main characteristic features of satellite imageries.
Answer:
The characteristic features of satellite imageries are :

• They can supply complete weather information and imagery of a full hemisphere at a time.
• Imageries can also be obtained in segments for detailed descriptions.
• They help in resource surveys, for eg-locating huge collection of fishes in ocean water, monitoring agricultural yields, etc.
• The informations collected by satellite imageries is digital, that can be easily analysed by computers.

OR.

Mention the merits and demerits of remote sensing.
Answer:
The merits of remote sensing are :

• Remote sensing helps to conduct surveys of regions from very long distances with the help of satellites, without coming in physical contact with the region.
• Surveys can be easily conducted during day or night time and on any kind of terrain.
• Most of the work in remote sensing is done with the help of computers and other sophisticated machines, Hence, very little man-power is required.

The demerits of remote sensing are :

• Remote sensing is a very expensive affair, as it includes use of highly sophisticated computers and machineries and satellite services.
• Remote sensing requires a special kind of training to analyse the images. Hence the images are not readable or usable for common people.
• Sometimes large scale engineering maps cannot be prepared from satellite data which makes remote sensing data collection incomplete.

Group-E.

5. Answer any two questions from the following :

Question 1.
Describe with sketches three major landforms developed by erosional work of rivers.
Answer:
The different landforms developed by the erosional works of rivers are :

i. Gorge or V-shaped valley: In the upper course of the river, the down-cutting force is much more than lateral of side-cutting force of erosion. Hence the channel develops more depth than width, and takes the shape of a V-shaped valley.

ii Canyon or I-shaped valley: When the river flows through an arid region made up of nonresistant rocks, most of its energy is spent in down-cutting rather than widening of the valley. Thus the valley takes the shape of an ‘I’-shaped valley.

iii. Pot holes: Round disc-like depressions curved by the swirling water and rock fragments on the bed or floor of the river are called pot holes.

iv. Waterfalls : When water of the river falls freely from a height due to very steep slope, it is called a waterfall. They are further classified into rapids, cataracts and cascades.

Question 2.
Explain the factors responsible for the formation of equatorial low pressure belt and polar high pressure belts.
Answer:
The factors responsible for the formation of equatorial low pressure belt are:

• The sun gives its maximum heat to this region through perpendicular rays. Hence, air gets heated, lightened and rises up.
• Presence of huge water bodies and much heat leads to high rates of evaporation. The air gets filled with water vapour and becomes light.
• Rotation of the earth tends to deflect air due to coriolis force.
• Presence of vast forests add up to water vapour in the air due to transpiration.

The factors responsible for the formation of polar high pressure belts are :

• The sun gives the most inclined rays to the polar regions. Heat is very less, hence the air is very cold and heavy.
• There is very less water vapour in the air, as the rate of evaporation is very less.
• Some air from the adjacent sub-polar low pressure belts rise and descend towards the poles, and increase the density of air over there.

Question 3.
Give an account of occurance of orographic rainfall with suitable example and diagram.
Answer:
Orographic rainfall is typically found in hilly and mountainous regions. When the moisture lader winds blowing from the 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 rainfall caused due to hindrance or obstruction by a mountain is called orographic or relief rainfall. (‘Oro’-greek word meaning mountain).

Question 4.
Explain the causes responsible for the development of high tides and ebb.
Answer:
The causes responsible for the development of high tides and ebb 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 of high tide experience ebbs or low tides.

ii. Effect of centrifugal force for 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. The regions lying perpendicular to the regions of high tides experience ebbs or low 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.

2. Answer any two questions from the following :

Question 1.
State the differences between the physical characteristics of North and South Indian rivers.
Answer:
The differences between the physical characteristics of the North and South Indian rivers are :

North Indian Rivers	South Indian Rivers
1. The North Indian rivers originate from the Himalayan range. Hence they are both rainfed and snowfed.	1. The South Indian rivers originate from the plateau region. Hence they are only rainfed.
2. The rivers are perennial, as they are both rainfed and snowfed.	2. The rivers tend to dry up in the dry season. Hence, they are non-perennial.
3. Most of the rivers exhibit their upper, middle and lower courses. Hence, they are ideal rivers.	3. Most of the rivers do not exhibit the three courses prominently. Hence, they are not ideal rivers.
4. The rivers are very long. They form ‘V’ and ‘I’-shaped valleys in the upper course.	4. The rivers are not very long. They mostly run through rugged regions and form less deep valleys.
5. The rivers are navigable in the middle and lower courses as the rivers are perennial and these regions have very gentle slope.	5. The rivers are not navigable as they are non perennial, and flow over rugged terrain.
6. These rivers have more number of tributaries.	6. These rivers have less number of tributaries.
7. These rivers carry a huge amount of silt and hence form big deltas at their mouth.	7. These rivers carry comparatively lower amount of silt, and hence form smaller deltas.

Question 2.
Give a brief account of alluvial and black soils of India.
Answer:

Alluvial soil	Black soil
1. Formed by deposition of sand, silt clay and organic matter brought down and deposited by rivers.	1. Formed by weathering of basalt rocks.
2. The colour of the soil varies from lightbrown to dark-grey.	2. The colour of the soil varies from black to dark-brown.
3. Found in the river valleys of India, especially along the middle and lower courses.	3 . Found in the plateau region of Maharashtra, parts of Gujarat and Madhya Pradesh, parts of Andhra Pradesh, Karnataka and Tamil Nadu.
4. Alluvial soil is best for growing crops like rice, wheat, sugarcane, jute, etc.	4. Block soil is best for growing crops like cotton, tobacco, jowar, wheat, etc.

Question 3.
State favourable physical conditions required for cultivation of wheat.
Answer:
The favourable physical conditions required for cultivation of wheat are :

• Temperature: Wheat prefers temperature around 155°c. The temperature should be low at the time of sowing, but as the time of harvesting approaches, higher temperature (about 21°c-26°c) is required for ripening of the crop.
• Rainfall: Wheat thrives well in areas receiving an annual rainfall of about 75cm – 100 cm. In areas receiving rainfall less then 50cm, the deficiency is recovered by irrigation.
• Frost: There should be atleast 100 frost-free days. Long gloomy or foggy weather is harmful for crop.
• Soil: Chernozem is the best suited soil for wheat. It also grows well in light clayey or heavy loamy soil.
• Land: Wheat grows well in well-drained slightly rolling plains

Question 4.
Discuss the importance of transportation system in India.
Answer
The importance of transportation system in India are –

• Transport system helps in moving agricultural products, industrial raw materials, finished manufactured goods, etc to the required regions.
• In helps in transportation of labor and other necessary things for the development of agricultural, industrial and other sectors.
• It makes different products available to all the corners of the country, so that uniform development can be made possible.
• It helps in growth of new towns and bigger cities and hence brings about urbanisation.
• It helps to remove regional disparities and inequalities.
• It makes administrative works easier.
• It helps to raise the National Income and bring about socio-economic development of the country.

Group-F.

Locate the following with appropriate symbols and names on the given outline map of India. Attach the map with the answer script.

1. Vindhya mountain
2. Loktak Lake
3. River Mahanadi
4. One-rainshadow region
5. One mangrove forest region.
6. One desert soil region.
7. One sugarcane producing region of north India.
8. One heavy engineering industrial centre of eastern India.
9. Vishakhapathnam Port.
10. A megacity of western coast.

OR
Answer any ten of the following questions :

1 Name the longest river of South India.
Answer: Godavari.

2 Which is the largest lagoon in the eastern coast of India?
Answer: Chilika lake in Odisha.

3 Name one tributary of Indus that flows through Punjab plain.
Answer: River Sutlej.

4 In which month kalbaisakhi occurs in India?
Answer: April-May.

5 Name a state having laterite soil.
Answer: Karnataka, Kerala, Madhya Pradesh.

6 What type of natural vegetation grows on saline soil of India?
Answer: Mangrove vegetation.

7 Name one plantation crop produced in India.
Answer: Tea, coffee.

8 Where is the largest petro-chemical industry of India located?
Answer: Gujarat.

9 Name the most populous state of India according to 2011 census.
Answer: Uttar Pradesh.

10 What is the name of the international Airport of West Bengal.
Answer: Netaji Subhas Chandra Bose International Airport.

11 What are the dry river vallays of the deserts called?
Answer: Wadis.

12 In which layer of the atmosphere, disturbances are found?
Answer: Troposphere.

13 Name the highest peak of South India.
Answer: Dodabetta Peak.

14 Name and iron and steel industrial centre of West Bengal.
Answer: Kulti, Burnpur, Durgapur.

Detailed explanations in West Bengal Board Class 10 Geography Book Solutions Chapter 2.2 Layers of the Atmosphere offer valuable context and analysis.

WBBSE Class 10 Geography Chapter 2.2 Question Answer – Layers of the Atmosphere

Answer in short : 2 Marks

Question 1.
Name the different layers of the atmosphere.
Answer:
The different layers of the atmosphere are – Troposphere, Stratosphere, Mesosphere, Ionosphere or Thermosphere and Exosphere.

Question 2.
What is the Tropopause?
Answer:
Tropopause is the transition zone between the troposphere and the stratosphere. It extends for about 2-3 km. Here the temperature remains constant.

Question 3.
What is the Stratopause?
Answer:
Stratopause is the transition zone between the stratosphere and the mesosphere. Temperature in this zone remains constant.

Question 4.
What is the mesopause ?
Answer:
Mesopause is the transition zone between the mesosphere and the ionosphere or the thermosphere. Temperature in this zone remains constant.

Question 5.
What is the ozone layer ?
Answer:
There is a layer in the stratosphere at a height of 20-45 km, which has a high concentration of ozone gas. This portion of the stratosphere is called the ozone layer or the ozonosphere.

Question 6.
Describe the exosphere.
Answer:
The exosphere lies above the thermosphere and extends up to 960 km. It gradually merges with the interplanetary space.

Question 7.
What is normal lapse rate?
Answer:
A lapse rate is the rate at which temperature of the atmosphere decreases as the altitude increases in troposphere. Temperature decrease at the rate of 6.4°C per 1000 mt. in the troposphere.

Question 8.
What is the Van Allen radiation belt ?
Answer:
Energetic charged particles mostly originated from solar wind are captured by and held around the planet earth called Van Allen radiation belt. Earth has two such belts.

Question 9.
What do you mean by nacreaous cloud ?
Answer:
One of the polar stratospheric clouds, that consist of only ice crystals are called nacreous cloud. These are not harmful. These are mostly observed during twillight. These are not precipitation cloud.

Answer in briefly : 3 Marks

Question 1.
Describe the Troposphere.
Answer:
The lower-most layer of the atmosphere lying closest to the earth’s surface is called the Troposphere. It extends up to 18 km at the equator and 8 km at the poles. Temperature decreases by 6.4°C with rise of every 1000 m or 1 km. This is called the lapse rate of temperature. Most of the weather phenomena occur in this zone. Eg. – clouds, rainfall, storms etc.

Question 2.
Describe the stratosphere.
Answer:
The second layer of the atmosphere that lies above the troposphere and extends up to 80 km above the earth’s surface is called the stratosphere. In this zone, temperature goes on increasing with increase in height (about 4°C for every 50 km). A significant concentration of ozone gas is found in this layer, known as the Ozonosphere. Stratosphere has very less atmospheric disturbances. Some cirrus clouds form in the lower levels of this layer.

Question 3.
Describe the mesosphere.
Answer:
The third layer of the atmosphere that lies above the stratosphere is known as the mesosphere. This zone is marked by decrease in temperature with height. This is the coldest layer of the atmosphere. Meteors that come from the outer space towards the earth get burnt within this layer.

Question 4.
What are the characteristics of the ozone layer?
Answer:
The ozone layer is a part of the stratosphere. The main characteristics of this layer are :

1. Ozone constitutes about 1% of the stratospheric air.
2. Ozone is produced by the action of solar radiation on ordinary oxygen atoms.
3. Ozone layer acts as a shield, protecting us by absorbing most of the harmful ultra-violet rays of the sun.
4. Density of ozone gas is expressed by the ‘Dobson’ unit (DU). Lowest density of the layer is found in the equatorial region.

Question 5.
What do you mean by ozone depletion and ozone hole.
Answer:
Depletion or breaking of ozone molecules in the atmosphere is known as ozone depletion.

1. Average natural concentration of ozone dropped by 50% in 1987.
2. In some areas, the ozone layer totally disappeared which resulted in formation of ozone-less patches. These hollows are called ozone holes.
3. The chloro fluoro carbons (CFCs) are the chief culprits causing ozone depletion.

Question 6.
Mention the characteristics of the lonosphere.
Answer:
The layer of the atmosphere lying above the mesosphere is called the ionosphere or thermosphere. The characteristics of this layer are :

1. This layer extends up to 500 km above the mesopause.
2. The gases absorb X-rays and Ultra-violet rays and the temperature increases.
3. Radio waves are reflected back from this layer, thus helping in radio communication.
4. Auroras or strange interesting lights are produced in the ionosphere. These are called Aurora Borealis in the northem hemisphere and Aurora Australis in the southern hemisphere.

Answer in details :

Question 1.
Discuss the layers of the atmosphere.
Answer:
[Write about all the layers of the atmosphere discussed previously.]

Detailed explanations in West Bengal Board Class 10 Geography Book Solutions Chapter 2.1 Concepts of Atmosphere offer valuable context and analysis.

WBBSE Class 10 Geography Chapter 2.1 Question Answer – Concepts of Atmosphere

Answer in short : 2 Marks

Question 1.
What is atmosphere?
Answer:
The thick blanket of air surrounding the earth, extending to a height of about 10,000 km above its surface, is known as the atmosphere. It is hold in place by the gravitational force of the earth.

Question 2.
What are Aerosols?
Answer:
Aerosols are very fine solid particles that remain suspended in the air. They act as the base of condensation for rainfall, snowfall, fog, dew, mist etc. They absorb solar radiation and keep the atmosphere warm. They are responsible for reflection of sunlight causing dawn and twilight. They also reflect light and make the sky appear blue.

Question 3.
Name the major gases of the atmosphere.
Answer:
The main gases of the atmosphere are : Nitrogen (78.084%), Oxygen (20.946%), Argon (0.934 %), Carbon dioxide (0.033 %).
Other gases present are : Neon, Helium, Krypton, Xenon, Hydrogen, Methane, Nitrous oxide, Radon, Ozone etc. Amongst these, Nitrogen, Argon, Neon, Helium, Krypton and Xenon are known as noble or inert gases.

Question 4.
What are the importances of oxygen in the atmosphere?
Answer:
Oxygen occupies about 21 % of the atmosphere. Importances of this gas are:

1. Oxygen helps to support life.
2. It helps to provide heat and energy in living organisms.
3. It helps in burning of fire.
4. It helps in the process of oxidation.
5. It causes rusting of iron.

Question 5.
Mention the importances of nitrogen gas in the atmosphere.
Answer:
Nitrogen occupies about 78 % of the atmosphere. Its importances are :

• Protein synthesis in living organisms.
• Increasing soil fertility.
• Manufacturing fertilisers.

Question 6.
Mention the importances of carbon dioxide.
Answer:
Carbon dioxide occupies a negligible percentage (0-033 %) in the atmosphere, but it is a very important gas.

1. It helps in photosynthesis and formation of glucose in plants.
2. It helps in carbonation of rocks during weathering.
3. It controls atmospheric temperature.
4. It controls or influences the climate.
5. It helps in weathering of limestone.

Question 7.
What is the homosphere ?
Answer:
According to D. S. Lal, “the term homosphere means the zone of homogenous composition’. It refers to that part of the atmosphere, where the composition is uniform.

Question 8.
What is the heterosphere?
Answer:
The atmosphere above the homosphere up to a height of 10,000 km is not uniform in composition with reference to its chemical composition and proportion. This part of the atmosphere is known as the heterosphere.

Question 9.
Why are the inert gases called so ?
Answer:
Gases like Nitrogen, Argon, Neon, Helium, Krypton and Xenon do not react with the components of atmosphere and the earth’s surface under normal circumstances. Hence they are called ‘inert gases’.

Question 10.
What is density of the atmosphere?
Answer:
The amount of gas molecules or the mass of gas molecules present in a unit volume of the atmosphere is known as the density of the atmosphere.

Answer in briefly : 3 Marks

Question 1.
What are the importances of water vapour in the atmosphere?
Answer:

1. Water vapour not only absorbs the sun’s incoming radiation (insolation), but also absorbs the heat radiated back by the earth, thus keeping the atmosphere warm.
2. It helps in formation of clouds, fog, dew, rainfall, snowfall etc.
3. Amount of water vapour influences occurrence of rainfall, snowfall, storms, and other environmental activities.
4. It helps the hydrological cycle to function properly.

Question 2.
Describe the importances of dust particles in the atmosphere.
Answer:
Dust particles mix with the atmosphere from various sources like – soil particles, salt particles from seas, solid particles coming out of cars and chimney smoke, cinder, ash etc. from volcanoes, ash from forest fires etc.
Importances of these particles in the atmosphere are :

• The dust particles act as the base of condensation for the formation of clouds, fog, mist, dew, rainfall, snowfall etc.
• They reflect and refract light.
• They help in occurrence of dawn, twilight and help the sky appear blue.
• They absorb insolation and back radiation from the earth and help to keep the atmosphere warm.

Question 3.
Mention the characteristics of the atmosphere.
Answer:
The main characteristics of the atmosphere are :

1. The atmosphere extends up to 10,000 km above the surface of the earth.
2. Density of the atmosphere reduces with height.
3. This contains the most important components that are inevitable for plant and animal life.
4. The atmosphere is invisible, but its presence can be felt evidently.

Question 4.
What are the characteristics of the ozone layer?
Answer:
Ozone gas is concentrated in the stratosphere at an altitude of 25-50 km above the earth’s surface. This layer is also called the ozonosphere. The characteristics are :

• 90% of ozone gas lies in this layer.
• It filters the ultra-violet rays that comes from the sun.
• It protects the biotic world from damage and disaster.
• Density of ozone gas is expressed in Doloson Unit (DU).
• Density of ozone gas is 250 DU near the equator, 350 DU in the mid latitudes and 450 DU in the polar regions.

Answer in details : 5 Marks

Question 1.
Name the main components of the atmosphere and discuss about them.
Answer:
The components of the atmosphere can be classified into two parts :
(a) Permanent components : The permanent components mainly constitute the gaseous elements those proportion does not change in the atmosphere.
They are : Nitrogen (78.084%), Oxygen (20.946%), Argon (0.934%), Carbon dioxide (0.033 %) and other gases like Nitrogen, Neon, Helium, Hydrogen, Xenon, Krypton, Methane, Radon, Ozone etc.

(b) Variable components : These include :
i) Water vapour : Amount of water vapour varies from place to place, time to time and depends on factors like heat, presence of water bodies, wind speed, humidity etc.

ii) Dust particles : Tiny solid particles coming from dust, salt grains, pollen grains, smoke, soot etc. remain suspended in the air in different amounts in different places. These are also called aerosols.

iii) Carbon dioxide : CO₂ is an important variable gas. Currently it constitutes about 0.03 %. of the atmosphere. It is a potent green house gas and plays a vital role in controlling the earth’s surface temperature.

Question 2.
Classify the layers of the atmosphere according to temperature.
Answer:
The atmosphere has been classified into five layers by Pattersen according to temperature.
i) Troposphere : The troposphere extends up to 18 km in the equatorial region to 7-8 km in the polar region above the earth’s surface. Temperature of this layer reduces by 6.4°C for every 1000 ~m rise in altitude. The lowest temperature

recorded here is -80°c at the highest limits of the troposphere near the equator.

ii) Stratosphere: This layer is above the troposphere, and is separated by the tropopause. Temperature of this layer goes on increasing with rise in altitude. It spreads up to 50 km above the earth’s surface. Temperature reaches to 0°C at the highest levels of the stratosphere. This layer is void of clouds and rainfall. A concentrated layer of ozone gas is found within this layer.

iii) Mesosphere : After the stratosphere, the mesosphere lies up to 80 km above the earth’s surface. This is the last limit of the homosphere. Temperature decreases with increase in altitude. This layer lies between the stratopause and the mesopause.

iv) Ionosphere or Thermosphere : This layer spreads up to 500 km from the earth’s surface after the mesopause. Temperature increases rapidly in this layer with rise in altitude, and reaches about 1200°C at the upper limits. In this layer, constant interaction of ultra violet rays, x-rays, α-rays, β-rays and γ-rays cause ionisation of the gases.

v) Exosphere : This layer spreads from 500-750 km above the earth’s surface.

Question 3.
Differentiate between the Homosphere and the Heterosphere.
Answer:

Homosphere	Heterosphere
i. The ratio of component gases of the atmosphere remains more or less same up to 88 km altitude. This layer is called the homosphere.	i. The ratio of component gases of the atmosphere does not remain the same beyond 88 km altitude. This layer is called the heterosphere.
ii. It spreads from 0-88 km above the earth’s surface.	ii. It spreads from 88-10,000 km above the earth’s surface.
iii. It comprises the troposphere, stratosphere, mesosphere and parts of the thermosphere.	iii. It comprises parts of thermosphere, the exosphere and magnetosphere.
iv. It consists of gases, water vapour and dust particles.	iv. It consists of very little traces of water vapour and dust particles. The gases mostly lie in ionised forms.
v. All the weather conditions and changes occur within 6 km of the homosphere.	v. No weather changes are noticed in the heterosphere.
vi. Lower layers of the homosphere support life and related activities. The ozone layer protects the earth from sun’s harmful ultraviolet rays.	vi. The ionised gases of the heterosphere help in transmission of radio waves, thus helping to run mobiles, wireless sets, radios and other devices.

Multiple Choice Questions (MCQ) : 1 Mark

Question 1.
The tropopause occurs at the equator at a height of :
(A) 5 km.
(B) 20 km.
(C) 18 km.
(D) 25 km.
Answer:
(C) 18 km.

Question 2.
97 % of the atmosphere lies within _____ km. of the surface of the earth :
(A) 50 km.
(B) 29 km.
(C) 5 km.
(D) 15 km.
Answer:
(B) 29 km.

Question 3.
The lower layer lonosphere is known as :
(A) Troposphere
(B) Stratosphere
(C) Ozonosphere
(D) Thermosphere
Answer:
(D) Thermosphere

Question 4.
The Mediterranean region receives rainfall :
(A) From trade winds in summer
(B) From trade winds in winter
(C) From westerlies in winter
(D) By convection in summer
Answer:
(C) From westerlies in winter

Question 5.
The atmospheric layer which reflects radio waves is called :
(A) Exosphere
(B) Stratosphere
(C)Troposphere
(D)Thermosphere
Answer:
(C)Troposphere

Question 6.
Atmosphere gets heated up :
(A) In the early morning
(B) At mid day
(C) At 2:00 pm.
(D) In the late evening
Answer:
(C) At 2:00 pm.

Question 7.
The most important component of the atmosphere which causes many weather phenomena is :
(A) Oxygen
(B) Carbon dioxide
(C) Nitrogen
(D) Water vapour
Answer:
(D) Water vapour

Question 8.
The lower layer of the atmosphere is known as :
(A) Mesosphere
(B) Stratosphere
(C) Ionosphere
(D) Troposphere
Answer:
(D) Troposphere

Question 9.
Tropopause is the zone that separates :
(A) Earth’s surface and Troposphere
(B) Troposphere and Stratosphere
(C) Stratosphere and lonosphere
(D) Earth’s surface and lonosphere
Answer:
(B) Troposphere and Stratosphere

Question 10.
Ionosphere is :
(A) The lowest region of the atmosphere
(B) The highest region of the atmosphere
(C) The middle most region of the atmosphere extending from 40 km. to 75 km.
(D) None of the above
Answer:
(B) The highest region of the atmosphere

Question 11.
The tropopause is situated at a height of over the equator
(A) 10 km.
(B) 15 km.
(C) 18 km.
(D) 22 km.
Answer:
(C) 18 km.

Question 12.
Most of the weather phenomena take place in the :
(A) Stratosphere
(B) Ionosphere
(C) Troposphere
(D) Mesosphere
Answer:
(C) Troposphere

Question 13.
________ of the effective atmosphere is found up to the height of 29 km.:
(A) 29 %
(B) 35 %
(C) 90 %
(D) 97 %
Answer:
(D) 97 %

Question 14.
Percentage of argon in the atmosphere is :
(A) 1 %
(B) 1.5 %
(C) 0.30 %
(D) 0.93 %
Answer:
(D) 0.93 %

Question 15.
Which one of the following is lowermost layer?
(A) Stratosphere
(B) Troposphere
(C) Troposphere or Stratosphere
(D) It is not certain
Answer:
(B) Troposphere

Question 16.
Normal Lapse rate is supposed to be:
(A) 6.5°C per 100m
(B) 6.5°C per 10m
(C) 6.5°K per 100m
(D) 6.0°K per 100m
Answer:
(A) 6.5°C per 100m

Question 17.
The average height of the troposphere over the poles is around :
(A) 16 km
(B) 14 km
(C) 8 km
(D) 6 km
Answer:
(D) 6 km

Question 18.
Medium and high frequency radio waves are reflected by which layer?
(A) E layer
(B) G layer
(C) F layer
(D) All of these
Answer:
(C) F layer

Question 19.
Isobars are :
(A) The lines of equal atmospheric pressure
(B) The lines of unequal atmospheric pressure
(C) The parallel lines of atmospheric pressure
(D) None of the above
Answer:
(A) The lines of equal atmospheric pressure

Question 20.
What is the characteristic of planetary winds:
(A) These flow from the belts of high pressure to the belts of low pressure
(B) These flow from the belts of low pressure to the belt of high pressure
(C) These do not flow to any centre of pressure
(D) None of these
Answer:
(A) These flow from the belts of high pressure to the belts of low pressure

Question 21.
Wind in the southern hemisphere deflects towards left :
(A) Due to rotation of the earth
(B) Due to temperature
(C) Due to heating
(D) None of these
Answer:
(A) Due to rotation of the earth

Question 22.
The instrument used for measuring the atmospheric pressure is called:
(A) Barometer
(B) Hygrometer
(C)Altimeter
(D) Thermometer
Answer:
(A) Barometer

Question 23.
The mountaineers climbing the high peaks carry:
(A) Helium
(B) Nitrogen
(C) Hydrogen
(D) Oxygen
Answer:
(D) Oxygen

Question 24.
The sub-tropical high pressure belts are also known as :
(A) Doldrums
(B) Roaring forties
(C) Torrid zone
(D) Horse latitudes
Answer:
(B) Roaring forties

Question 25.
Besides the local winds and permanent winds, another type of winds are :
(A) Prevailing winds
(B) Horizontal winds
(C) Vertical winds
(D) Periodic winds
Answer:
(D) Periodic winds

Question 26.
If the incoming solar radiation is 100 % then scattering by dust particles is :
(A) 27 %
(B) 2 %
(C) 6 %
(D) None of these
Answer:
(C) 6 %

Question 27.
The amount of heat needed to raise the temperature of one gram of substance by 1°C is called :
(A) Specific heat
(B) Relative heat
(C) Absolute heat
(D) None of these
Answer:
(A) Specific heat

Question 28.
Horse latitudes are found between the latitudes :
(A) 5°N to 5°S
(B) 25°-35° in both the hemisphere
(C) 30°-45° in both the hemisphere
(D) None of these
Answer:
(B) 25°-35° in both the hemisphere

Question 29.
The zone of _____ wind is also known as Hadley cells.
(A) Westerly
(B) Easterly
(C) Trade
(D) None of these
Answer:
(C) Trade

Question 30.
Which type of rainfall is called relief rainfall ?
(A) Convectional
(B) Orographic
(C) Cyclonic
(D) All of these
Answer:
(B) Orographic

Question 31.
Which of the following instruments is used for measuring the temperature?
(A) Barometer
(B) Thermometer
(C) Hydrometer
(D) Hygrometer
Answer:
(B) Thermometer

Question 32.
Anemometer is used to measure :
(A) The velocity of the earth
(B) The velocity of the waves
(C) The velocity of the winds
(D) The velocity of earthquake waves
Answer:
(C) The velocity of the winds

Question 33.
The actual mass of water vapour per unit volume of air is known :
(A) Relative humidity
(B) Absolute humidity
(C) Specific humidity
(D) Degree of saturation
Answer:
(B) Absolute humidity

Question 34.
The prevailing north-western westerly winds which blow vigorously between 40° and 60° south latitudes throughout the year are known:
(A) Sirocco
(B) Roaring forties
(C) Harmattan
(D) Pampero
Answer:
(B) Roaring forties

Question 35.
About 34 per cent of insolation being returned to space as short waves are known as :
(A) Effective solar radiation
(B) The earth’s Albedo
(C) Heat Transfer
(D) Terrestrial heat balance
Answer:
(B) The earth’s Albedo

Question 36.
The boundary zone developed at or near the mass of warm air where an advancing cold air strikes and forces the warm air upward is called :
(A) Warm front
(B) Cold front
(C) Occuluded front
(D) Warm air mass
Answer:
(B) Cold front

Question 37.
The rate of temperature decreases (C°) in the atmosphere per 1000 metre ascent is :
(A) 3.6° C
(B) 6.4° C
(C) 7.4° C
(D) 8.6° C
Answer:
(B) 6.4° C

Question 38.
Inversion of temperature is :
(A) Increase of temperature with altitude
(B) Decrease of temperature with altitude
(C) Uniform temperature
(D) Decrease of temperature with latitudes
Answer:
(A) Increase of temperature with altitude

Question 39.
The albedo of earth is :
(A) 25 %
(B) 35 %
(C) 45 %
(D) 55 %
Answer:
(B) 35 %

Question 40.
The total annual insolation is greatest at –
(A) The tropic of Cancer
(B) The tropic of Capricorn
(C) The equator
(D) The arctic circle
Answer:
(D) The arctic circle

Question 41.
The dry adiabatic lapse rate is :
(A) 6.4°C
(B) 10°C
(C) 8.5°C
(D) 2°C
Answer:
(B) 10°C

Question 42.
Jet stream is a :
(A) Warm Current
(B) Cold Current
(C) Local Wind
(D) Upper air westerlies
Answer:
(D) Upper air westerlies

Question 43.
The type of rainfall common at equatorial region is :
(A) Convectional
(B) Orographic
(C) Cyclonic
(D) Relief
Answer:
(A) Convectional

Question 44.
Doldrum is a zone of :
(A) Intertropical Convergence
(B) Intertropical Divergence
(C) Local wind
(D) Frontolysis
Answer:
(A) Intertropical Convergence

Question 45.
The highest temperature is recorded by :
(A) Mercurial thermometer
(B) Hot thermometer
(C)Alcohol thermometer
(D) Minimum thermometer
Answer:
(A) Mercurial thermometer

Question 46.
The lowest temperature is recorded by :
(A) Maximum thermometer
(B) Mercurial thermometer
(C) Alcohol thermometer
(D) None of these
Answer:
(C) Alcohol thermometer

Question 47.
What is the name of the scale meant for recording weather conditions?
(A) Fahrenheit
(B) Barometer
(C) Hydrometer
(D) Opisometer
Answer:
(A) Fahrenheit

Question 48.
Another scale used for recording weather conditions is known as :
(A) Hygrometer
(B) Hydrometer
(C) Opisometer
(D) Centigrade
Answer:
(D) Centigrade

Question 49.
Which of the following components of the atmosphere has increased during the last 200 years?
(A) Oxygen
(B) Water vapour
(C) Carbon dioxide
(D) Nitrogen
Answer:
(C) Carbon dioxide

Question 50.
The velocity of wind is recorded by :
(A) altimeter
(B) Barometer
(C) Anemometer
(D) Aneroid barometer
Answer:
(C) Anemometer

Question 51.
Horse latitudes lie :
(A) In the vicinity of 30° latitude both north and south of the equator
(B) In the vicinity of 50° latitude both north and south of the equator
(C) Between 50° and 60° latitude both north and south of equator
(D) None of these
Answer:
(A) In the vicinity of 30° latitude both north and south of the equator

Question 52.
When warm air moves into a region of cold air it leads to the formation of :
(A) Cold front
(B) Warm front
(C) Cyclone
(D) Anticyclone
Answer:
(B) Warm front

Question 53.
Hurricanes are generally :
(A) Active over land
(B) Active over the sea
(C) Travelling in families
(D) Dust storms
Answer:
(B) Active over the sea

Question 54.
The tropical cyclones of the Bay of Bengal are usually called :
(A) Typhoons
(B) Hurricanes
(C) Depressions
(D) Willy willy
Answer:
(A) Typhoons

Question 55.
Jet Stream blows :
(A) From west to east
(B) From east to west
(C) From north to south
(D) None of these
Answer:
(A) From west to east

Question 56.
In which region does rainfall occur throughout the year?
(A) Equatorial region
(B) Polar region
(C) Sub-polar region
(D) Middle-latitude region
Answer:
(A) Equatorial region

Question 57.
China type (Cw) has dry winter season because :
(A) Cool dry winds blow from interior of the continent
(B) There are no clouds
(C) Temperature is low
(D) Humidity is low
Answer:
(A) Cool dry winds blow from interior of the continent

Question 58.
Tropical deserts receive scanty rainfall because:
(A) They are away from the equator
(B) They do not have clouds
(C) Trade winds blow from the hot interior of the continent
(D) Cool currents blow along the coast
Answer:
(C) Trade winds blow from the hot interior of the continent

Question 59.
Which of the following is not a tropical desert:
(A) Kalahari
(B) Atacama
(C) Arabia
(D) Mongolia
Answer:
(D) Mongolia

Question 60.
Conduction is a process :
(A) That conducts heat from warmer to the cooler region until the two objects coming into contact get the same temperature
(B) That conducts heat from cooler to the warmer region
(C) That does not conduct heat to any of the objects coming into contact
(D) None of the above
Answer:
(A) That conducts heat from warmer to the cooler region until the two objects coming into contact get the same temperature

Question 61.
Humidity is the result of :
(A) Evaporation
(B) Transpiration
(C) Presence of heat
(D) Presence of moisture content in the air
Answer:
(D) Presence of moisture content in the air

Question 62.
Specific humidity is :
(A) The indicator of density of water vapour
(B) The maximum water content existing in the atmosphere
(C) It is the ratio of the mass of water vapour present to the total mass of air
(D) None of the above
Answer:
(C) It is the ratio of the mass of water vapour present to the total mass of air

Question 63.
What is relative humidity ?
(A) It is the ratio of specific humidity
(B) It is the indicator of moisture content of atmosphere
(C) It is the indicator of density of water vapour
(D) None of the above
Answer:
(A) It is the ratio of specific humidity

Question 64.
Annual range of temperature is maximum in :
(A) Equatorial region
(B) Sub-tropical region
(C) Middle latitudes
(D) Polar regions
Answer:
(C) Middle latitudes

Question 65.
The winds blowing from subtropical high pressure to sub-polar low pressure are :
(A) Westerlies
(B) Easterlies
(C) Polar winds
(D) Jet Stream
Answer:
(B) Easterlies

Question 66.
Doldrum belt is the region of :
(A) High pressure and strong winds
(B) Moderate pressure
(C) Low pressure and calm conditions
(D) None of these
Answer:
(C) Low pressure and calm conditions

Question 67.
Animometer is :
(A) An instrument that measures the wind speed
(B) An instrument that measures the air masses
(C) An instrument that measures speed
(D) An instrument that measures velocity
Answer:
(A) An instrument that measures the wind speed

Question 68.
Trade winds are :
(A) Moisturous
(B) Hot and wet
(C) Dry
(D) Wet
Answer:
(C) Dry

Question 69.
Beaufort scale is used to measure :
(A) Air pressure
(B) Wind velocity
(C) Wind direction
(D) Humidity
Answer:
(B) Wind velocity

Question 70.
The Torrid Zone lies between :
(A) The Equator and the Tropic of Cancer
(B) The Equator and the Tropic of Capricorn
(C) The Tropic of Cancer and the Tropic of Capricorn
(D) Precipitation and natural vegetation
Answer:
(C) The Tropic of Cancer and the Tropic of Capricorn

Question 71.
Nitrogen and Oxygen constitute of the total gaseous composition of the atmosphere.
(A) 93 %
(B) 95 %
(C) 97 %
(D) 99 %
Answer:
(D) 99 %

Question 72.
Which of the following is a Greenhouse gas ?
(A) Carbondioxide
(B) Ozone
(C) Oxygen
(D) Nitrogen
Answer:
(A) Carbondioxide

Question 73.
Most of the ultraviolet rays one absorbed by
(A) Hydrogen
(B) Nitrogen
(C) Ozone
(D) Carbondioxide
Answer:
(C) Ozone

Question 74.
________ is a permanent gas in the atmosphere.
(A) Carbondioxide
(B) Ozone
(C) Nitrogen
(D) Hydrogen
Answer:
(C) Nitrogen

Question 75.
Atmospheric water vapour content is highest in the
(A) Temperate region
(B) Polar region
(C) Equatorial region
(D) Tropical region
Answer:
(D) Tropical region

Question 76.
The English word ‘atmosphere’ comes from the green word ‘atmos’, which means-
(A) Air
(B) Vapour
(C) Evaporation
(D) Envelop of gases
Answer:
(B) Vapour

Question 77.
The sky appears blue due to selective scattering of solar radiation by-
(A) Salt particles
(B) Dust particles
(C) Both A and B
(D) None of these
Answer:
(B) Dust particles

Question 78.
Troposphere contains about ______ of the total gaseous mars of the atmosphere.
(A) 70 %
(B) 75 %
(C) 80 %
(D) 85 %
Answer:
(B) 75 %

Question 79.
Which of the following is also called the convective region?
(A) lonosphere
(B) Ozonosphere
(C) Troposphere
(D) Mesosphere
Answer:
(C) Troposphere

Question 80.
The wind velocity increases with height in the –
(A) Troposphere
(B) Stratosphere
(C) Stratopause
(D) lonosphere
Answer:
(A) Troposphere

Question 81.
The thickness of the stratosphere is highest at the –
(A) Poles
(B) Tropics
(C) Equator
(D) All of these
Answer:
(A) Poles

Question 82.
Which gas protects us from the harmful ultraviolet rays ?
(A) Nitrogen
(B) Oxygen
(C) Ozone
(D) Carbondioxide
Answer:
(C) Ozone

Question 83.
The credit for the discovery of ionosphere goes to –
(A) Napier Shaw
(B) Picardy
(C) Kennelly and Heaviside
(D) Teisserence de Bort
Answer:
(C) Kennelly and Heaviside

Question 84.
During the winter season, the stratosphere is warmest between the latitudes
(A) 50°-60°
(B) 50°-65°
(C) 50°-70°
(D) 50°-75°
Answer:
(A) 50°-60°

Question 85. ‘Aurora Borealis’ is produced in the
(A) Exosphere
(B) Ionosphere
(C) Mesosphere
(D) Stratosphere
Answer:
(B) Ionosphere

Question 86.
Match the following

Answer:

Question 87.
helps to keep the temperature of the earth’s surface moderate.
(A) Gases
(B) Water vapour
(C) Particulate matter
(D) All of these
Answer:
(B) Water vapour

Question 88.
Which of the following is an important feature of the Troposphere?
(A) It is isothermal in character
(B) There is maximum concentration of ozone
(C) There is a decrease of temperature with increase in altitude at a mean lapse rate of about 6.5°C
(D) There is a steep rise in temperature
Answer:
(C) There is a decrease of temperature with increase in altitude at a mean lapse rate of about 6.5°C

Question 89.
The outermost layer of the atmosphere is known as
(A) Exosphere
(B) lonosphere
(C) Mesosphere
(D) Ozonosphere
Answer:
(A) Exosphere

Question 90.
The gases which are predominant in the exosphere are
(A) Hydrogen and Neon
(B) Hydrogen and Ozone
(C) Hydrogen and Methane
(D) Hydrogen and Helium
Answer:
(D) Hydrogen and Helium

Question 91.
Troposphere, Stratosphere and Mesosphere are subdivisions of the
(A) Homosphere
(B) Heterosphere
(C) Chemosphere
(D) Pyrosphere
Answer:
(A) Homosphere

Question 92.
The atmosphere receives most of its energy from
(A) Sun
(B) Long wave terrestrial radiation
(C) Albedo
(D) Short wave terrestrial radiation
Answer:
(A) Sun

Question 93.
The transfer of heat through the molecules of matter in any body is called
(A) Radiation
(B) Convection
(C) Conduction
(D) Advection
Answer:
(B) Convection

Question 94.
The process of transfer of energy from one body to another without the aid of any material is called –
(A) Conduction
(B) Radiation
(C) Convection
(D) Advection
Answer:
(C) Convection

Question 95.
What percentage of outgoing longwave terrestrial radiation is absorbed by atmosphere?
(A) 60 %
(B) 70 %
(C) 80 %
(D) 90 %
Answer:
(D) 90 %

Question 96.
The increase in the concentration of CO₂ in the atmosphere will increase the
(A) Heat
(B) Greenhouse effect
(C) Radiation
(D) Evaporation
Answer:
(B) Greenhouse effect

Question 97.
The earth’s surface recelves maximum solar energy at about
(A) 11: 00 am
(B) 12 Noon
(C) 1: 00 pm
(D) 2: 00 pm
Answer:
(B) 12 Noon

Question 98.
The thermal inversion in the upper air is caused by the presence of
(A) Carbondioxide
(B) Ozone layer
(C) Water vapour
(D) None of these
Answer:
(B) Ozone layer

Question 99.
Which of the following surface receives very low insolation ?
(A) Snow cover
(B) Sand
(C) Black soil
(D) Forest
Answer:
(A) Snow cover

Question 100.
The horizontal distribution of temperature is represented and studied with the help of –
(A) Isotherms
(B) Isobars
(C) Isohyte
(D) Isohayline
Answer:
(A) Isotherms

Question 101.
The weight of air on unit area of the earth is called
(A) Air weight
(B) Air pressive
(C) Air mass
(D) Air volume
Answer:
(B) Air pressive

Question 102.
The atmospheric pressure is maximum at the
(A) Coastal areas
(B) Interior parts of continents
(C) Sea level
(D) All of these
Answer:
(C) Sea level

Question 103.
The standard air pressure at sea level is –
(A) 1018.25 m
(B) 1021.25 m
(C) 1013.25 m
(D) 1015.25 m
Answer:
(C) 1013.25 m

Question 104.
Which of the following pressure belt is thermally inducted?
(A) Subtropical high pressure belt
(B) Equatorial low pressure belt
(C) Subpolar low pressure belt
(D) Both ‘A’ and ‘C’
Answer:
(B) Equatorial low pressure belt

Question 105.
The winds blowing almost in the same direction throughout the year are called
(A) Prevailing winds
(B) Seasonal winds
(C) Local winds
(D) Variable winds
Answer:
(A) Prevailing winds

Question 106.
Winds blowing in a particular locality are called
(A) Seasonal winds
(B) Local winds
(C) Mountain winds
(D) Land and sea breeze
Answer:
(B) Local winds

Question 107.
Which winds are famous for there steady direction and wind speed?
(A) Westerlies
(B) Easterlies
(C) Polar winds
(D) Trade winds
Answer:
(D) Trade winds

Question 108.
The subtropical high pressure belt is the source of –
(A) Polar winds
(B) Trade winds
(C) Local winds
(D) Westerlies
Answer:
(B) Trade winds

Question 109.
The continent having the greatest monsoonal influence is –
(A) North America
(B) Asia
(C) South America
(D) Australia
Answer:
(B) Asia

Question 110.
Which of the following wind prevails on the eastern slopes of the Rocky mountains in Wyoming and Montana?
(A) Santa Ana
(B) Mistral
(C) Sirocco
(D) Chinook
Answer:
(D) Chinook

Question 111.
Which of the following is an intensely hot and dry wind of the Asiatic and African deserts?
(A) Khamsin
(B) Sirocco
(C) Simoom
(D) Harmatian
Answer:
(C) Simoom

Question 112.
Which of the following is a cold north-western wind that blows towards the western mediteranean basin from higher elevations?
(A) Mistral
(B) Bora
(C) Blizzard
(D) Harmattan
Answer:
(A) Mistral

Question 113.
The most important form of suspended water droplets caused by condensation is
(A) Fog
(B) Ice
(C) Cloud
(D) Frost
Answer:
(C) Cloud

Question 114.
is the most common form of precipitation
(A) Snow
(B) Rainfall
(C) Sleet
(D) Hail
Answer:
(B) Rainfall

Question 115.
Which of the following is a warm weather phenomena associated with lightning and thunder?
(A) Convectional rainfall
(B) Orographic rainfall
(C) Frontal rainfall
(D) All of these
Answer:
(A) Convectional rainfall

Question 116.
Which of the following rainfall occur due to ascent of air, forced by mountain barrier?
(A) Convectional rainfall
(B) Orographic rainfall
(C) Cyclonic rainfall
(D) All of these
Answer:
(B) Orographic rainfall

Question 117.
Indian monsoon is the best example of
(A) Convectional rainfall
(B) Cyclonic rainfall
(C) Orographic rainfall
(D) None of these
Answer:
(C) Orographic rainfall

Question 118.
Southern plateau in the east of Western Ghats is the example of
(A) Inversion of rainfall
(B) Cloud instability
(C) Maximum rainfall line
(D) Rain shadow area
Answer:
(D) Rain shadow area

Question 119.
The precipitation associated with cold fronts is always in the form of
(A) Snow
(B) Drizzle
(C) Thunder shower
(D) Sleet
Answer:
(C) Thunder shower

Question 120.
Most of the rains of temperate regions are received through
(A) Cyclonic rainfall
(B) Orographic rainfall
(C) Convectional rainfall
(D) None of these
Answer:
(A) Cyclonic rainfall

Question 121.
Which of the following pressure belt is called ‘Horse latitude’ ?
(A) Polar high pressure belt
(B) Subpolar low pressure belt
(C) Subtropical high pressure belt
(D) Equatorial low pressure belt
Answer:
(C) Subtropical high pressure belt

Question 122.
Which of the following winds blows parallel to the isobars, generally at a height of 600 m ?
(A) Gradient wind
(B) geostrophic wind
(C) Invariable wind
(D) Surface wind
Answer:
(B) geostrophic wind

Question 123.
The direction of surface wind is usually controlled by
(A) Pressure gradient
(B) Rotation of the earth
(C) Deflection forces
(D) Both ‘A’ and ‘B’
Answer:
(D) Both ‘A’ and ‘B’

Question 124.
The zone extending 5°N to 5°S along the equator is called
(A) Doldrums
(B) Horse latitudes
(C) Trade wind
(D) Westerlies
Answer:
(A) Doldrums

Question 125.
Winter precipitation in the Northern part of India is an example of ______ rainfall.
(A) Orographic
(B) Monsoonal
(C) Convectional
(D) Cyclonic
Answer:
(D) Cyclonic

Question 126.
The monsoon region is located in the ______ rainfall zero.
(A) Mediterranean
(B) Trade wind
(C) Subtropical
(D) Midlatitude
Answer:
(B) Trade wind

Question 127.
______ is an example of atmospheric disturbance.
(A) Rain
(B) Cyclone
(C) Fronts
(D) Winds
Answer:
(B) Cyclone

Question 128.
Temperate cyclones are formed where
(A) Contrasting air masses generally meet
(B) Same air masses generally meet
(C) No air masses meet
(D) None of these
Answer:
(A) Contrasting air masses generally meet

Question 129.
Which of the following is a real temperate cyclone?
(A) Dynamic cyclone
(B) Thermal cyclone
(C) Secondary cyclone
(D) Both ‘A’ and ‘B’
Answer:
(A) Dynamic cyclone

Question 130.
The diameter of the temperate cyclone varies from
(A) 160-3200 km
(B) 170-3400 km
(C) 180-3600 km
(D) 190-3800 km
Answer:
(A) 160-3200 km

Question 131.
The vertical extent of an average cyclone is about
(A) 10-12 km
(B) 12-14 km
(C) 14-16 km
(D) 16-18 km
Answer:
(A) 10-12 km

Question 132.
Most of the cyclones and anticyclones in the westerly wind belt move from –
(A) East to West
(B) West to East
(C) North to East
(D) South to West
Answer:
(B) West to East

Question 133.
On an average, diameter of tropical cyclone ranges between
(A) 80-500 km
(B) 80-400 km
(C) 80-300 km
(D) 80-200 km
Answer:
(C) 80-300 km

Question 134.
Tropical cyclones affect the
(A) Interior areas of continents
(B) Coastal areas of continents
(C) Peninsular areas of continents
(D) Central areas of continents
Answer:
(B) Coastal areas of continents

Question 135.
Tropical cyclone develops in the regions
(A) of high latitudes
(B) of mid-latitudes
(C) Along the equator
(D) Lying between the tropics of Cancer and Capricorn
Answer:
(D) Lying between the tropics of Cancer and Capricorn

Question 136.
Tropical cyclones move from East to West under the influence of
(A) Easterlies
(B) Westerlies
(C) Polar winds
(D) Trade winds
Answer:
(D) Trade winds

Question 137.
________ develops in the Caribbean Sea and North Pacific Ocean during summer months.
(A) Hurricanes or Typhoons
(B) Tropical disturbances
(C) Tropical depressions
(D) Tropical storms
Answer:
(B) Tropical disturbances

Question 138.
_______ develops frequently in the Bay of Bengal and Arabian sea during the summer season.
(A) Tropical storms
(B) Tropical depressions
(C) Tropical disturbances
(D) Hurricanes or Typhoons
Answer:
(A) Tropical storms

Question 139.
Match the following :

Answer:

Question 140.
Tropical cyclones originate over warm oceans having average surface temperature of ______ during summer.
(A) 27° C
(B) 30° C
(C) 33° C
(D) 36° C
Answer:
(A) 27° C

Question 141.
Tropical cyclone influence the climatic conditions of India between
(A) April and September
(B) April and October
(C) April and November
(D) April and December
Answer:
(D) April and December

Question 142.
Which of the following is a funnel-shaped cyclone with thick clouds?
(A) Tornadoes
(B) Hurricanes
(C) Thunderstorms
(D) Depressions
Answer:
(A) Tornadoes

Question 143.
Auticyclones are vast areas of high pressure with a system of _______ surface winds.
(A) Diverging
(B) Converging
(C) Deformative
(D) Diffusing
Answer:
(A) Diverging

Question 144.
Auticyclones are indicative of –
(A) Humid weather
(B) Dry weather
C) Rainy weather
(D) Hot and dry weather
Answer:
(B) Dry weather

Question 145.
The diameter of anticyclones of mid-latitudes is about
(A) 2000 km
(B) 3000 km
(C) 4000 km
(D) 5000 km
Answer:
(B) 3000 km

Fill in the blanks : 1 Mark

1. Ozone layer was discovered by ________.
2. ‘El Nino’ means ________.
3. Barometer was discovered by ________.
4. A _____ is used to measure air pressure.
5. Air pressure is measured by the unit ________.
6. A ______ is used to measure aire temperature.
7. A ________ is used to measure humidity of air.
8. The westerlies are referred to as roaring forties along the ______ latitude.
9. the westerlies are referred to screaming sixties along the _______ latitude.
10. The _______ is a comparatively calur layer of atmosphere.
11. Van Allen radiation belt can be seen at an altitude of ________.
12. The temperature of the upper part of the mesosphere is about ________.
13. ________ are the chief ozone destroying gases.
14. The radio waves are reflected back to the earth from the ________.
15. Sea breeze blows during ________.
16. The _______ helps to detect rapid change in air pressure.
17. Pompero blows in the valley of river ________.
18. The _______ helps to measure wind speed.
19. In the tropical region, the deserts have been created on the side of the _______ continents.
20. The land breeze blows with the greatest speed during the ________.
21. If pressure gradient increases, wind speed ________.
22. By ferrel’s law, winds deflect towards the in the _______ southern hemisphere.
23. The mediterranearn region received rainfall during ________.
24. the cold wind blowing along the Adriatic Sea coast during winter is called ________.
25. The winds are called ‘snow eaters’.
26. The ________ winds are the heavy winds that descend along the mountain slopes.
27. Connectional rainfall occurs from _______ clouds.
28. Smoke and fog together produce ________.
29. Relative humidity is measured by the instrument called ________.
30. _______ is a rain shadow area in India.
Answer:
1. Charles Fabry and Henri Buisson
2. Christ child
3. Torricelli
4. Barometer
5. Milibar
6. Thermometer
7. Hygrometer
8. 40°
9. 60°
10. Stratosphere
11. 4000 km
12. (-) 93°C
13. CFCs
14. Ionosphere
15. Day time
16. Barogram
17. Rhine
18. Anemometer
19. Western
20. Early morning
21. Increases
22. Left
23. Winter
24. Bora
25. Chinook
26. Katabatic
27. Cumulonimbus
28. Smog
29. Psychrometer
30. Shillong/Eastern slope of Western Ghats

State True or False : 1 Mark

1. The CO₂ absorbs the ultraviolet rays of the sun. [ ]
2. The water vapour present in the atmosphere leads to the scattering of light. [ ]
3. Hydrogen gas concentrates at an altitude of 200-1100 km above the earth’s surface. [ ]
4. The meteors coming from outer space one burnt in the mesosphere of the earth’s atmosphere. [ ]
5. The jet planes fly through the stratosphere. [ ]
6. The thickness of the troposphere is about 8 km near the equator. [ ]
7. CFCs are emitted by refrigerators, air conditioners etc. [ ]
8. The tropopause lies between the stratosphere and mesosphere. [ ]
9. The boiling point of water by the Fahrenheit scale is 212°F. [ ]
10. High pressure prevails in the Arctic circle region. [ ]
11. Orographic rainfall occurs in the windward slope of the mountains. [ ]
12. In tropical regions, cyclones occur due to formation of fronts. [ ]
13. Inversion of temperature occurs in the stratosphere. [ ]
14. A local wind named Fohn blows in Alps mountainous region. [ ]
15. Due to the coriolis force, winds are deflected towards the right in the northern hemisphere, and towards the left in the southern hemisphere. [ ]
16. The 30°-35° latitudes are also known as horse latitudes. [ ]
17. The jet stream influences the monsoon winds. [ ]
18. Low pressure prevails in the centre of anticyclones. [ ]
19. The centre of the cyclone is known as an eye. [ ]
20. The westerlies blow with higher speed in the southern hemisphere than the northern hemisphere. [ ]
21. The anticyclone moves in a clockwise direction in the northern hemisphere. [ ]
22. Cyclones commonly occur in China. [ ]
Answer:
1. Flase
2. Flase
3. Flase
4. True
5. True
6. Flase
7. True
8. Flase
9. True
10. Flase
11. True
12. Flase
13. True
14. True
15. True
16. True
17. True
18. Flase
19. True
20. True
21. True
22. Flase

Answer in few words : 1 Mark

Question 1.
What is the envelop of air around the earth called?
Answer:
Atmosphere.

Question 2.
Which gas is needed by green plants?
Answer:
Carbon dioxide.

Question 3.
Which gas saves us from the harmful Ultraviolet rays ?
Answer:
Ozone.

Question 4.
Which is the densest layer of the atmosphere ?
Answer:
Troposphere.

Question 5.
What lies between the stratosphere and mesosphere?
Answer:
The Stratopause.

Question 6.
Which force is responsible for exertion of atmospheric pressure on the earth’s surface?
Answer:
The gravitational force of the earth.

Question 7.
What is the horizontal movement of air called ?
Answer:
Wind.

Question 8.
What is the other name for permanent winds ?
Answer:
Planetary winds.

Question 9.
Name two winds blowing in opposite directions.
Answer:
The easterlies or trade winds and the westerlies.

Question 10.
What type of a wind is the monsoon wind ?
Answer:
Periodic wind.

Question 11.
How is humidity represented ?
Answer:
In percentage.

Question 12.
By which process does water vapour in the air change into water ?
Answer:
Condensation.

Question 13.
What is ‘dew’?
Answer:
Tiny droplets of water that remain suspended in the air.

Question 14.
What is sleet?
Answer:
Rain and snow falling together.

Question 15.
Name two rain-bearing clouds.
Answer:
Cumulus and nimbus.

Question 16.
Where does relief rainfall occur?
Answer:
Windward side of mountains.

Question 17.
Does warm air hold more or less water vapour ?
Answer:
More water vapour.

Question 18.
Does speedy winds increase the rate of evaporation?
Answer:
Yes.

Question 19.
What is a saturated air ?
Answer:
Air that holds the maximum amount of water vapour that it can hold.

Question 20.
Name the instruments measuring humidity.
Answer:
Hygrometer.

Question 21.
What is measured by a Six’s Maximum and Minimum thermometer?
Answer:
Maximum and minimum temperatures of a day.

Question 22.
On what does the amount of rainfall depend ?
Answer:
Moisture content of the air.

Question 23.
What is the side of the mountain facing away from the wind called?
Answer:
Leeward side.

Question 24.
Which is the most widespread form of rainfall ?
Answer:
Orographic or relief rainfall.

Question 25.
Where are the meeting of warm and cold fronts common ?
Answer:
The middle latitudes.

Question 26.
Which season receives most of the rainfall on the earth’s surface?
Answer:
Summer.

Question 27.
Do the borders or interiors of the continents get more rainfall ?
Answer:
Borders of the continents.

Question 28.
Which is the hottest part of the earth ?
Answer:
The equatorial region.

Question 29.
Among on-shore and off-shore winds, which one has less moisture content?
Answer:
Off-shore winds.

Question 30.
What happens to relative humidity when temperature decreases ?
Answer:
Relative humidity increases.

Detailed explanations in West Bengal Board Class 10 Geography Book Solutions Chapter 1.4 Works of Wind offer valuable context and analysis.

WBBSE Class 10 Geography Chapter 1.4 Question Answer – Works of Wind

Answer in short : 2 Marks

Question 1.
Name the areas where wind action is predominant.
Answer:
Wind action is predominant in :
(a) Desert regions (tropical and subtropical)
(b) Arid regions adjacent to deserts.
(c) Coastal regions.

Question 2.
On what factors does the erosive actions of wind depend ?
Answer:
Erosive action of wind depends on :
(a) Wind speed (b) Amount of sand, pebbles etc. carried by the wind, (c) Rock structure of the region (d) Vegetation cover (e) Heat, humidity and amount of rainfall.

Question 3.
Name some famous deserts of the world.
Answer:
Sahara of Africa, Atacama of Chile, Gobi of Mongolia, Soneran of North America etc.

Question 4.
What is a ventifact ?
Answer:
In deserts where wind blows from a single direction, large rocks standing in the path of the wind get polished on one side due to abrasion. This one side polished face with sharp edges is called a ventifact.

Question 5.
What is loess?
Answer:
Plains formed by deposition of fine sand particles carried by wind far away from the place where they belong, are called loess or loess plains.

Question 6.
What is a dreikanter?
Answer:

In deserts where winds blow from different directions in different seasons, the big rocks lying in the path of the wind get polished on all sides due to abrasion. This multi sided polished faced with sharp edges is called a dreikanter.

Question 7.
What is an oasis ?
Answer:
In a desert, when sand is deflated from an area continuously, creating a deep hollow or basin, the level of grand water may get exposed. Thus water may seep out from this place forming a shallow water body. This is known as an oasis. A few plants may grow here. A few settlements may also develop.

Question 8.
What is a playa?
Answer:
Shallow lakes created in depressions surrounded by hills in a desert region are called playa.

Question 9.
What is a bajada?
Answer:
The plain land developed adjacent to a pediment by deposition of eroded materials in a deserted region, is called a bajada.

Question 10.
What is a pediment?
Answer:
When high plateaus or mountains in desert areas are lowered by wind abrasion, the sloping stony plains formed at the foot of the mountain is called a pediment.

Question 11.
What are mesa and butte?
Answer:

‘Mesa’ means ‘table’ in Spanish. In desert areas, if plateaus are highly dissected by wind erosion, the flat topped landforms thus formed are called mesa. When mesa gets eroded and reduced in size, they are called butte.

Question 12.
What is a gour?
Answer:
Due to wind abrasion, when the lower parts of big rocks get more eroded than the higher parts, the feature thus formed resembles like a mushroom. This narrow based and broad-topped landform is called a gour.

Question 13.
What is a wadi?
Answer:
In desert regions, narrow river valleys created by rainwater are called wadis. They remain dry for most of the year.

Question 14.
What is a ‘dhand’?
Answer:
In Rajasthan, low depressions created by deflation of sand by wind in desert regions are called ‘dhand’.

Question 15.
Name the northernmost hot desert and the driest hot desert of the world.
Answer:
Northernmost hot desert – Gobi desert, Driest hot desert – Atacama desert of Chile.

Question 16.
What is the rate of average rainfall in the hot deserts of the world?
Answer :
Averge rainfall in the hot deserts of the world is around $25 \mathrm{~cm}$ per year.

Question 17.
What kind of ocean currents pass beside the deserts of the world ?
Answer:
Except for the deserts in Asia, all the other deserts of the diferent continents of the world have cold currents flowing beside them.

Question 18.
What is a ‘Blow-out’ ?
Answer:
In a desert, when tonnes of sand are blown away by winds, thus creating a hollow or depression which is quite deep, is called a ‘Blow-out’. This is an erosional feature found in a desert. Eg. – Katara in Egypt.

Question 19.
Which desert in the world has the largest moving sand dunes ?
Answer:
Rub-al-Khali desert of Saudi Arabia, Asia.

Question 20.
What is an inselberg ?
Answer:
In a desert, the rocky surfaces get reduced by abrasion and attrition of wind action. But, if a resistant rock is present in the path of the wind, it cannot be eroded and lowered equally with the surrounding rock surfaces. Hence, they stand out like isolated or island mountains within the deserts. These are called inselbergs.

Question 21.
What are Barkhans?
Answer:
The crescent shaped sand dunes created in perpendicular direction to the direction of wind in a desert, are called Barkhans. Eg. – Such crescent sand dunes can be seen in the Sahara and Kalahari deserts in Africa.

Question 22.
What are Seif dunes?
Answer:
Seif dunes are sand dunes produced in a desert lying parallel to the dirction of wind. They can be several kilometres long but only a few metres wide.

Question 23.
What is an erg ?
Answer:
The huge deserts formed only of sand particles are known as ergs in Sahara. The same landforms are known as kums in Turkistan. Eg.-Rub-at-khali in Saudi Arabia is the largest erg in the world.

Question 24.
What is reg?
Answer:
The deserts formed of rock fragments of various sizes are known as reg in Algeria.

Question 25.
What are sand dunes?
Answer:
The sand particles moved by wind action in a desert and dumped in huge heaps are called sand dunes.

Question 26.
What is a desert pavement?
Answer:
A desert region composed of unequal pieces of rock fragments is called desert pavement.

Answer briefly : 3 Marks

Question 1.
What are the reasons for predominant wind action in arid regions?
Answer:
Although wind blows over the whole of the earth, its action is predominant in arid regions. This is because :

1. No obstacle in wind direction : In desert regions, due to lack of rainfall, there is no or very less vegetation cover. Thus wind blows unhindered with high speed.
2. Loose and exposed soil : Lack of vegetation makes the soil loose and exposed to wind action.
3. High diurnal range of temperature : Great difference between day and night temperature causes rocks to crack and break due to contraction and expansion. This makes the work of the wind easier.

Question 2.
What are the different methods of wind erosion?
Answer:
The different methods by which the wind erodes are:

1. Deflation : This refers to the process of remaining unsorted dust and sand particles by blowing out by winds.
2. Abrasion : By this method, the sand and rock particles carried by the wind rub, scour, groove, cut and polish any rock surface that comes in its way.
3. Attrition : By this method, the rock and sand particles carried by the wind strike against each other, break and reduce in size.

Question 3.
Differentiate between Yardang and Zeugen.
Answer:

Question 4.
Mention the factors on which the erosive power of wind depends.
Answer:
The erosive power of wind depends on – (i) Wind speed (ii) Amount and nature of sand, pebbles and rock fragments carried by the wind (iii) Nature of rock beds (iv) Vegetation cover (v) Heat, humidity and amount of rainfall.

Question 5.
What is a pediment ?
Answer:
When high plateaus or mountains in deserts are highly eroded and lowered by wind abrasion, the sloping stony plains formed at the foot of the mountains is called a pediment.

Question 6.
Differentiate between a Pediment and a Bajada.
Answer:

Pediment	Bajada
i. Formed by combined work of wind and water at the foot of the mountains due to erosion.	i. Formed by combined action of wind and water by deposition of sand, clay, pebbles etc.
ii. Lies at the foot of mountains highlands in deserts.	(ii) Lies in the stretch between a pediment and playa in a desert.
iii. It is a hard rocky region.	iii. It is formed by deposition of loose materials like sand, pebbles, gravels etc.
iv. Pediments are slightly concave in shape.	iv. Bajada are slightly convex and look something like alluvial cones.

Question 7.
What is a blow-out?
Answer:

The basins or hollows which are formed by sweeping away of loose, light and sandy particles by winds, are called blow-outs or deflation basins. They are known as ‘dhand’ in Rajasthan. The largest blow-out of the world is the Qattara depression in Egypt.

Question 8.
Differentiate between barkhans and seif dunes.
Answer:

Question 9.
What is loess plain ?
Answer:
An yellowish sediment produced by wind-blown silt deposition, usually in the size range of 20-50 micrometer, loosly cemented by calcium carbonate is called loess. The flat regions covered by such deposits are called loess plains. This helps to make farm land very fertile.

Question 10.
Why wind action also active in the coastal regions ?
Answer:
Action of wind is very active in desert area. But it is also active in coastal area, because :
1 . Open and extensive coastline helps to blow the sea breeze towards the land with no obstraction and cause erosion of coastal area.
2. Sea waves are help to break the rocks of coastal area into small granules which can be then easily blow away by the wind.
3. Uninterrupted wind blown through the coastal area carried sand prevent in the coast and formed landforms like sand dunes in the coastal region.

Question 11.
What is an Inselberg ?
Answer:

The German term inselberg means ‘Island mountain’. They are outstanding, rounded, steep-sided residual hills rising abruptly from nearby eroded flat surface. Their height may vary from 10-300 m.

Question 12.
Name the landforms formed by combined action of wind and water.
Answer:
Landforms formed by combined action of wind and water are : wadi, playa, pediment and bajada.

Question 13.
Name the regions where wind action is predominant in creation of new landforms.
Answer:
The regions where wind action is predominant in creation of new landforms are:

1. Deserts (Tropical and sub-tropical regions)
2. Semi-arid and dry regions adjacent to deserts.
3. Coastal areas.

Question 14.
How is sand particles formed in desert regions ?
Answer:
In deserts, due to high temperature fluctuations between day and night, the barren exposed rocks are severely expanded and contracted regularly. This causes breaking of the rocks into smaller parts and finally leads to the formation of sand. The pebbles and fragments of rocks borne by the wind hit against the rocky walls of mountains, hills or other land surfaces. This causes high rates of erosion, and thus leads to formation of sand. Presence of hard minerals in the broken rock fragments cause exploding action when they colide with the rock surfaces. This also helps in creation of sand.

Answer in details : 5 Marks

Question 1.
Name and describe the landforms formed by wind depostion.
Answer:
The different landforms formed by wind deposition are :
(i) Longitudinal or Seif dunes : Low but long ridges of sand particles lying parallel to the wind direction are called seif dunes. They may be 40-70 m. in height, about 100 m in width, and a few kilometres in length.

(ii) Transverse dunes: When dunes are formed perpendicular or transversely to the wind direction, they are called transverse dunes. They are common in deserts where sand supply is abundant and wind speed is moderate.

(iii) Barkhans : Crescentshaped sand dunes that receive wind from only one direction are called barkhans. They have two horns opposite to the wind direction.
(iv) Loess : Fine sand particles, carried by winds and deposited far away from their place of origin, forming extensive plants are called loess.

Question 2.
What are the main causes of spread of deserts or desertification?
Answer:
The main causes of desertification are :
(a) Physical causes :

1. Drought : Regular and repeated droughts may damage the soil permanently, preventing any vegetative growth, hence bringing in desertification.
2. Climatic changes : Green house effect and global warming may affect the climate of an area and advance desertification.
3. Soil erosion : Removal of top soil may also cause desertification.
4. Presence of mountains : Presence of mountains may obstruct moisture-laden winds to cause rainfall. Hence deserts may be created in the rain shadow areas.

(b) Man-made causes :

1. Over-grazing : Over-grazing may remove the vegetative cover of the soil permanently, and cause desertification.
2. Over-cultivation : Unscientific cultivation may cause removal of nutrients from the soil and cause further extension of deserts.
3. Uncontrolled irrigation : Over-irrigation may cause soils to become saline, loose fertility and tend to turn into deserts.
4. Deforestation : Cutting down of trees remove vegetative cover and cause desertification.

Question 3.
What are the methods of controlling desertification?
Answer:
The process of desertification is very difficult to stop totally. But certain steps may be taken for its control :

1. Controlled grazing : Grazing should be controlled, especially in arid and semiarid regions.
2. Cultivation : Cultivation of drought resistant crops must be encouraged near deserts.
3. Afforestation : Trees should be planted to cover up exposed areas.
4. Irrigation : Controlled irrigation helps to improve soil quality.
5. Others : Other steps that can be taken are – rain water harvesting, preventing salinity of soil, proper planning of land use, increasing consciousness among people etc.

Question 4.
What are the causes of desertification of Sahara? What are the remedial steps taken?
Answer:
Sahara in Africa is the largest hot desert of the world, covering about 91,00,000 sq km area.
Causes of desertification : (i) Extreme sand storms (ii) Lack of rainfall due to global warming (iii) Reduction of agriculture at the borders of the desert.

Preventive measures :

1. The Federal state and the govt. of Nigeria has taken up annual tree planting programmes. Free plants are distributed to be planted in agricultural fields and houses.
2. Heavy reforestation programmes are taken up in dry areas of Mali, Mauritania, Niger, Sudan, Senegal, Chad, Ethiopia etc.
3. Involvement of ladies, youth and students in reforestation and awareness programmes.

Question 5.
Mention the causes of spread of the Thar desert and the preventive measures taken.
Answer:
The Thar desert spreads over 2.34 million sq. km. in India over west Rajasthan, Gujarat, south west Punjab and parts of Haryana.

Causes of spread of desert : (i) High speed winds (ii) Large moving sand dunes (iii) High diurnal range of temperature (iv) Low rainfall (v) High rate of evaporation.
Preventive measures : (i) Reforestation is being done on the hill slopes in this region according to several government programmes. (ii) Artifical grasslands are being created to prevent movement of sand dunes in Barmer, Jaisalmer, etc. (iii) Trees that grow fast, are being planted to meet the demand of fuel wood of local people in Jaisalmer, Jhuijhunu etc.(iv) The Rajasthan canal has been constructed to irrigate and reclaim infertile land.

Question 6.
Name and describe three landforms created by erosive action of wind.
Answer:
The landforms created by erosive action of wind are :

(i) Gour : When the lower portions of a huge rock mass is eroded away much more compared to the upper portions, the landform thus formed resembles a mushroom. Such top heavy features are called ‘Gour’.
(ii) Yardang : When hard and soft rocks lie in bands in vertical direction to the direction of the wind the softer rocks get eroded very fast, while the harder rocks act like resistances and get less eroded. The harder rocks have rugged surfaces. These are called ‘Yardangs’.

(iii) Zeugen : When hard and soft rocks lie in bands perpendicular to the direction of wind, the soft rocks are eroded away very fast. The hard rocks stand out like broad topped and narrow-based landforms. These are called ‘Zeugens’.

Question 7.
Describe the different landforms formed by combined action of wind and water in desert areas.
Answer:
The different landforms formed by the combined action of water and wind in a desert region are :
(i) Wadi : In deserts sudden torrential rains lead to formation of valleys through which the collected rain water may flow like a river. In dry season, these valleys also remain dry.

(ii) Playa : Playas are small lakes found in deserts. They are highly saline and the water cannot be used for agricultural or household purposes.
(iii) Pediment : Pediment refers to the eroded and lowered plainlands that lie at the foot of the mountains.

(iv) Bajada : Bajada refers to the deposition of materials, brought down by wind as well as water and deposited beyond the pediment.

Multiple Choice Question (MCQ) : 1 Mark

Question 1.
Loess is commonly formed by deposition of
(A) Silt by wind
(B) Sand by wind
(C) Silt by rivers
(D) Dust by volcanoes
Answer:
(B) Sand by wind

Question 2.
The crescent shaped sand dunes are called
(A) Barkhans
(B) Seif
(C) Yardang
(D) Arete
Answer:
(A) Barkhans

Question 3.
Landforms, not associated with wind erosion is
(A) Rock pedestal
(B) Zeugen
(C) Yardang
(D) Dunes
Answer:
(D) Dunes

Question 4.
Pediments are formed in
(A) Arid regions
(B) Coastal regions
(C) Glacial regions
(D) Valley regions
Answer:
(A) Arid regions

Question 5.
Gour can be found in
(A) Coastal area.
(B) Arid region
(C) Glaciated region
(D) Island area
Answer:
(B) Arid region

Question 6.
Lakes formed within sand dunes are called
(A) Dhands
(B) Dhrians
(C) Playas
(D) Shots
Answer:
(A) Dhands

Question 7.
Wadis are
(A) Mountain Valley
(B) Flower Valley
(C) Depressional Valley
(D) Dry Valley
Answer:
(D) Dry Valley

Question 8.
Bajada is a
(A) Erosional plain formed by wind
(B) Depositional plain formed by wind and water
(C) Erosional plain formed by river
(D) Depositional plains formed by glaciers
Answer:
(B) Depositional plain formed by wind and water

Question 9.
Yardang is formed by
(A) Glacial deposition
(B) Marine deposition
(C) Wind erosion
(D) Sea erosion
Answer:
(C) Wind erosion

Question 10.
Isolated hard resistant rocks scatterd in plain deserts are called
(A) Monadnocks
(B) Inselbergs
(C) Drumlins
(D) Spur
Answer:
(B) Inselbergs

Question 11.
The steep-sided, deeply undercut, overhanging rock ridges separated from one another by long grooves in desert floors of relatively softer rocks are called
(A) Dreikanters
(B) Ventifacts
(C) Zeugens
(D) Yardangs
Answer:
(D) Yardangs

Question 12.
Wind windows and window bridges are ______ land forms.
(A) Transportational
(B) Erosion
(C) Depositional
(D) None of these
Answer:
(B) Erosion

Question 13.
Accumulation of sands between obstacles are called
(A) Sand shadows
(B) Sand drifts
(C) Sand dunes
(D) Ripple marks
Answer:
(B) Sand drifts

Question 14.
The wind-borne materials deposited beyond the limits of the deserts by wind action are called
(A) Sand dunes
(B) Loess
(C) Ripple marks
(D) Barkhans
Answer:
(B) Loess

Question 15.
The loess formation in China is most prominent in
(A) North China
(B) East China
(C) South China
(D) West China
Answer:
(A) North China

Question 16.
Wind erosion in the arid and semi-arid regions is assisted by
(A) Chemical weathering
(B) Mechanical weathering
(C) Biological weathering
(D) Differential weathering
Answer:
(B) Mechanical weathering

Question 17.
Wind erosion is largely controlled and determined by
(A) Wind velocity
(B) Compositions of rocks
(C) Nature of Vegetation
(D) All of these
Answer:
(D) All of these

Question 18.
The process of removing, lifting and blowing away dry and loose particles of sads and dusts by wind is called
(A) Deflation
(B) Abrasion
(C) Attrition
(D) Corrosion
Answer:
(A) Deflation

Question 19.
Which of the following rocks are called ‘gara’ in Sahara?
(A) Dreikanter
(B) Dunes
(C) Stone lattice
(D) Mushroom rocks
Answer:
(D) Mushroom rocks

Question 20.
Wind transports materials by the process of
(A) Suspension
(B) Saltation
(C) Traction
(D) All of these
Answer:
(D) All of these

Question 21.
The mineral abundantly found in sand duhes is
(A) Quartz
(B) Kaolin clay
(C) Feldspar
(D) Clay
Answer:
(A) Quartz

Question 22.
The dunes formed along coasts and margins of deserts are called
(A) Longitudinal dunes
(B) Transverse dunes
(C) Bankhan dunes
(D) Parabolic dunes
Answer:
(B) Transverse dunes

Question 23.
The sand dunes formed parallel to wind direction are called
(A) Transverse dunes
(B) Barkhan dunes
(C) Parabolic dunes
(D) Longitudinal dunes
Answer:
(D) Longitudinal dunes

Question 24.
Which of the sand dunes have two horns ?
(A) Nebkha
(B) Barkhan
(C) Seif
(D) Transverse dunes
Answer:
(B) Barkhan

Question 25.
The example of the most significant wind blown deposits is
(A) Sand dunes
(B) Loess
(C) Ripple marks
(D) Playa
Answer:
(B) Loess

Question 26.
Loess is known as ‘Limon’ in
(A) France
(B) Nebraska
(C) Australia
(D) China
Answer:
(A) France

Question 27.
‘Inselberg’ was first named by
(A) W. M. Davis
(B) L. C. King
(C) R. L. Parker
(D) R. A. Bagnold
Answer:
(B) L. C. King

Question 28.
Seif dunes were first named by
(A) L.C.King
(B) W. Penck
(C) W. M. Davis
(D) R. A. Bagnold
Answer:
(D) R. A. Bagnold

Question 29.
The dry river channels in arid regions are called
(A) Wadi
(B) Bolson
(C) Salina
(D) Loess
Answer:
(A) Wadi

Question 30.
The salt lakes found in arid regions are called
(A) Bolson
(B) Wadi
(C) Playa
(D) Dhand
Answer:
(C) Playa

Question 31.
The shifting dunes of Rajasthan are locally known as
(A) Dhrian
(B) Barchan
(C) Loess
(D) Blow out
Answer:
(A) Dhrian

Question 32.
Cresentic dunes are called
(A) Seif
(B) Barchan
(C) Loess
(D) Blow out
Answer:
(B) Barchan

Question 33.
Pediments are formed by the ______ works of wind and temporary stream.
(A) Erosional
(B) Transportational
(C) Depositional
(D) Erosional and Depositional
Answer:
(A) Erosional

Question 34.
The hard rocks standing like dames or hills is a desert are called
(A) Mushroom rock
(B) Inselbergs
(C) Yardangs
(D) Bajada
Answer:
(B) Inselbergs

Question 35.
‘Gara’ is formed by the action of
(A) River
(B) Glacier
(C) Wind
(D) Waves
Answer:
(C) Wind

Question 36.
Barchans get gradually converted to
(A) Akle dunes
(B) Seif
(C) Gara
(D) Wadi
Answer:
(B) Seif

Question 37.
Marusthali means
(A) Land of the dead
(B) Rainshadow region
(C) A land of heavy rainfall
(D) Lack of camels.
Answer:
(A) Land of the dead

Question 38.
Mesas are eroded further to form
(A) Zeugen
(B) Butle
(C) Inselberg
(D) Yardang
Answer:
(B) Butle

Question 39.
The dome shaped low hills present is the peneplain regions are called-
(A) Monad rocks
(B) Gara
(C) Yardang
(D) Till
Answer:
(A) Monad rocks

Question 40.
In peneplain, low lying hill of hard rocks remains as residual landform is called
(A) Yardang
(B) Zeugen
(C) Sand dunes
(D) Inselberg
Answer:
(D) Inselberg

Fill in the blanks : 1 Mark

1. The playa lakes in the arid regions of Africa are known as _______.
2. The playa lakes in the desert region of Rajasthan are known as _______.
3. The crescent-shaped sand dunes lying perpendicular to the wind direction are called _______.
4. The vast sandy deserts in Sahara, lacking any vegetation are called _______.
5. The playa lakes are known as _______ in the desert regions of Mexico.
6. _________ is the largest sandy desert of the world.
7. _________ dunes are created from seif dunes.
8. The desert research centre of India is located at _______.
9. The term ‘dreikanter’ means _______.
10. _______ is a cold desert in India.
11. Loess comes from a German word meaning _______.
12. _______ has its origin in the Arabic word meaning ‘Sword’.
13. Thick loess deposits are found in _________ in India.
14. The desert lakes in Sahara are known as _______.
15. Oases are formed by ________ action of wind.
Answer:
1. Shots
2. Dhand
3. Barkhans
4. Erg
5. Bolson
6. Rub-at-khali desert in Saudi Arabia
7. Barkhan
8. Jodhpur
9. Three-sided
10. Ladakh
11. Loose materials
12. Seif
13. M.P.
14. Shalts
15. Erosion

State True or False : 1 Mark

1. Barkhans mean crescent-shaped dunes. [ ]
2. The largest desert of the world is Sahara. [ ]
3. The action fo wind is mostly noticed in high mountains [ ]
4. Barkhans are formed by erosional action of winds. [ ]
5. The sand dunes along the coastal region of Kerala are called terres. [ ]
6. The largest deflation hollow of the world is Qatara. [ ]
7. The driest desert of the world is Sahara. [ ]
8. The rocky part of the Sahara desert is called hamada. [ ]
9. The region between two seif dunes is called gasi. [ ]
10. Oases are created due to abrasion of wind. [ ]
11. Pediment is a type of plain. [ ]
12. The loward slope of the ventifact is smooth and sharp. [ ]
13. The landforms looking like mushrooms found in deserts are called yardang. [ ]
14. The Salt water lakes of deserts are called wadies. [ ]
15. The Taklamakan Desert lies in China. [ ]
16. ‘Mesa’ means ‘Chair’ in Spanish. [ ]
Answer:
1. True
2. True
3. False
4. False
5. True
6. True
7. False
8. True
9. True
10. True
11. True
12. False
13. False
14. False
15. True
16. False

Match the following :

List 1	List 2
A. Sahara	i. Asia
B. Gobi	ii. Africa
C. Salina	iii. South America
D. Barkhan	iv. North America
E. Soneran	v. Kirghiz, Steppe region
F. Atacama	vi. Playa lake

Answer:

List 1	List 2
A. Sahara	ii. Africa
B. Gobi	i. Asia
C. Salina	vi. Playa lake
D. Barkhan	v. Kirghiz, Steppe region
E. Soneran	iv. North America
F. Atacama	iii. South America

Answer in few words : 1 Mark

Question 1.
What are sandy deserts known as ?
Answer:
Erg.

Question 2.
What are the moving sand dunes of Rajasthan called ?
Answer:
Dhrians.

Question 3.
What are rocky deserts known as ?
Answer:
Hamada.

Question 4.
What are ‘gours’ also known as ?
Answer:
Gara, or mushroom rocks or rock pedestals.

Question 5.
What are inselbergs?
Answer:
Outstanding rounded steep-sided residual rocks or hills in deserts.

Question 6.
What are deflation basins ?
Answer:
Hollows created in deserts by sweeping away or deflation of sand by wind.

Question 7.
What are dunes?
Answer:
Heaps of sand formed by wind deposition in deserts.

Question 8.
What are Barkhans?
Answer:
Crescent shaped sand dunes.

Question 9.
Which is the largest ‘hot’ desert of the world ?
Answer:
Sahara desert in Africa.

Question 10.
Where does the Thar desert lie in India ?
Answer:
West Rajasthan, Gujarat, South-western Punjab and parts of Haryana.

Practicing with West Bengal Board Class 10 Geography Book Solutions and West Bengal Board Class 10 Geography Question Paper 2020 alongside detailed explanations can lead to a deeper understanding of the subject.

WBBSE Class 10 Geography Question Paper 2020

Group-A.

1. Write the correct answer from the given alternatives: 1×14=14

Question 1.
The process by which, soil and rock layers move down along the slope of highlands by gravity is called:
a. Weathering
b. Gradation process
c. Endogenic processes
d. Mass wasting process
Answer:
d. Mass wasting process

Question 2.
In pediplain, low lying hills of hard rocks remain as residual landform is called :
a. Yardang
b. Zeugen
c. Sand dunes
d. Inselberg
Answer:
d. Inselberg

Question 3.
“Horse Latitude” is located at :
a. Equatorial low pressure belt
b. Sub-tropical high pressure belt
c. Sub-polar low pressure belt
d. Polar high pressure belt
Answer:
b. Sub-tropical high pressure belt

Question 4.
Diurnal range of temperature is maximum in :
a. Equatorial climatic region
b. Hot desert climatic region
c. Tropical Monsoon climatic region
d. Mediterranean climatic region
Answer:
b. Hot desert climatic region

Question 5.
The formation of ocean currents depend on :
a. Prevailing winds
b. Earth’s revolution
c. Sand banks
d. All of them are applicable
Answer:
a. Prevailing winds

Question 6.
The time difference between high and low tides at a place is nearly :
a. more than two hours
b. more than six hours
c. more than four hours
d. more than eight hours
Answer:
b. more than six hours

Question 7.
Carbon particles emitted by vehicles are controlled by use of :
a. Cyclone Separators
b. Electrostatic Precipitator
c. Scrubber
d. Coated Alumina
Answer:
c. Scrubber

Question 8.
Parallel of latitude, passing through the middle of India is :
a. Equator
b. Tropic of Capricorn
c. Prime Meridian
d. Tropic of Cancer
Answer:
d. Tropic of Cancer

Question 9.
The lake located, in between the deltas of Godavari and Krishna rivers is :
a. Kolleru
b. Pulicat
c. Chilka
d. Vembanad
Answer:
a. Kolleru

Question 10.
The most extensive method of irrigation, practiced in India is :
a. Wells and tube wells
b. Tanks
c. Canals
d. Sprinkler
Answer:
a. Wells and tube wells

Question 11.
Western disturbances occur in India during :
a. Summer season
b. Autumn season
c. Rainy season
d. Winter season
Answer:
d. Winter season

Question 12.
Salty sea breeze is needed for :
a. Sugar cultivation
b. Tea cultivation
c. Jute cultivation
d. Coffee cultivation
Answer:
a. Sugar cultivation

Question 13.
Petro-chemical industrial centre of West Bengal is located at :
a. Junput
b. Kolkata
c. Sankarpur
d. Haldia
Answer:
d. Haldia

Question 14.
The colour used for drawing of contour lines in topographical map is :
a. Brown
b. Black
c. Red
d. Blue
Answer:
a. Brown

Group-B.

1. If the statement is true, write ‘T’ and if false, write ‘F’ against the following answer any six: 1×6=6

1. The confluence of Alakananda and Bhagirathi rivers is at Devprayag.
Answer: True

2. Mistral is a warm local wind which blows over Rhone valley in France.
Answer: False

3. Floods occur in India in the years of El-Nino.
Answer: False

4. The position of sun, moon and earth along a straight line is known as syzygy.
Answer: True

5. Papers may be manufactured by recycling newspapers as raw material.
Answer: True

6. The soil composed of pebbles, sands and silts, found along the foothills of Siwalik is called bet.
Answer: False

7. For analysis of satellite imageries, use of computer is mandatory.
Answer: True

2. Fill in the blanks with suitable words answer any six: 1×6=6

1. The process of modifying landforms by combined action of erosion and weathering is called ……..
Answer: Gradation

2. Oases are formed by ………………… action of wind.
Answer: Erosional/Deflational/Blouring

3. With the increase of air pressure gradient, wind velocity ………..
Answer: Increases

4. The cold ocean water from polar region flows as ………………… current towards equator.
Answer: Cold

5 The longest national highway of India is NH …………..
Answer: 44

6. Indian Space Research Centre is situated at …………..
Answer: Thiruvananthapuram

7. In short, electronic waste is known as ………….. waste.
Answer: e

3. Answer in one or two words answer any six: 1×6=6

1. Name the largest valley glacier of the world.
2 Where in the atmosphere over the earth surface ozone hole was first discovered?
3 Name the southern-most mountain pass of Western Ghats.
4 What is the local name of the lagoons in Kerala coast?
5 Name the highest waterfall of India.
6 In which city of India underground rail first started its journey?
7 Which is the most populous state of India?
8 In what form the satellite imagery is produced?
Answer:
1. Lambert glacier in Antarctica.
2. Antarctica
3. Pal ghat (Palakkad gap)
4. Kayal
5. Kunchikal waterfalls of karnataka
6. Kolkata
7. Uttar Pradesh
8. Digital form

4. Match the Left Column with the Right Column:1×4=4

A	B
1. Ratna	a. Pine
2. Coniferous forest	b. Murmagaon
3. Railway coach manufacturing centre	c. High-yielding variety rice seed
4. Iron ore exporting port	d. Perambur

Answer:
1-c, 2-a , 3-d, 4 -b

Group-C.

3. Answer the inflowing in brief (Alternatives should be noted): 2×6=12

Question 1.
What is Plunge Pool?
OR Define Loess.
Answer:
The depression or hole created at the foot of a waterfall due to falling or plunging of water along with rock fragments with high velocity, is known as a plunge pool.

OR.
Plains formed by deposition of fine sand particles carried by wind far away from the place where they belong, are called loess or loess plains. Eg-A loess plain has been formed along the valley of river Hwang Ho in China, due to deposition of sand blows away from the gobi desert.

Question 2.
What is relative humidity?
OR, What do you mean by Perigean tide?
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 of water vapour that the air can hold at that particular temperature, is known as relative humidity. It is expressed as a percentage.

Relative humidity
\(=\frac{\text { Actual amount of water vapour present in air }}{\text { Maximum amount of water vapour the air can hold at that temperature }} \times 100\)
Or
\(\text { Relative humidity }=\frac{\text { Absolute humidity }}{\text { Humidity capacity }} \times 100\)
Or
A perigean tide occurs when the moon comes closest to the earth (on a new moon or full moon day) while revolving around the earth on its orbit. The strongest perigean tide occurs three or four times a year when a perigee (nearest position of the moon to the earth) coincides with a spring tide (When the sun, the moon and the earth are nearly aligned in every two weeks).

Question 3.
What is a landfill in waste management?
OR
Define municipal wastes.
Answer:
The method of discarding wastes in approved grounds, filling up the huge holes dug to bury the wastes callected, is called land-filling. Land-filling 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 requires a large vacant land and produces strong methane and other gases, and cause contamination problems.
OR.
The wastes generated in the urban areas, or municipal areas. are known as municipal wastes. These include trash of garbage from households, schools, offices, markets, restaurants and other public places; obsolute computers, mobiles and other electronic goods; furniture and old fashioned clothes etc.

Question 4.
Mention two characteristic features of desert vegetation in India.
OR.
What do you mean by “Dun”?
Answer:
Characteristics of desert vegetation in India are :

• It is found in Rajasthan, Kachch and Kthiawar Peninsular region of gujarat and the rain shadow area of Decan Plateau.
• The vegetation is very sparsely spread.
• The leaves of the plants are reduced to thorns due to lack of water. The roots are very long to absorb underground water. The stems are flashy and have a waxy coating over them.

OR.
The valleys lying in the siwalik range are called ‘Duns’ or ‘Doons’. The Siwalik range has been formed much later than the Himadri and Himachal Himalayas. During the formation of the siwalk, the rivers that were flowing ran the higher Himalyan ranges got interupted 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 5.
Define ancillary industry.
OR
Name the two terminal centres of the longest inland waterways in India.
Answer:
The industries which supply their finished products as raw materials for some other industries or support the growth of other industries are called basic industries, and the industries which receive these raw materials or are supported by these basic industries, are called ancillary industries. Eg-Ancillary industries for the automobile industry are-tyre industry battery industry, glass industry etc.
OR.
The longest inland waterway of india (also called National Waterway 1) lies along the Ganga-Bhagirathi-Hooghl river system. It is 1,620 km long, lying between Prayagraj in Allahabad in the north to Haldia in West Bengal (Sagar) in the south.

Question 6.
What do you mean by sensor?
OR.
State two uses of topographical maps.
Answer:
A sensor is a specialised camera that is installed in a satellite in order to take photographs of the earth. It can be of two types. An active sensor uses its own energy for illumination and helps the satellite to capture images at night. A passive sensor can help the satellite to capture images only when the sun is illuminating the earth.
OR.
The uses of topographical maps are :

• It helps to understand and study the physical characteristics of the region.
• It helps to understand and analyse the different cultural features (roads, settlements, etc.) of the same area with respect to the physical features present there.
• It helps to analyse the relation between man and nature, and helps to plan for economic development.

Group-D.

Give brief explanatory answer (Alternatives should be noted):-

Question 1.
Discuss in brief about three processes of river transportational activity.
OR.
Mention the relationship between Jet stream and Indian Monsoon system.
Answer:
The river transports its load by the following processes:

• Traction: The heavier and large rock fragments are forced to flow down along the river water by rolling on the floor of the river channel due to gravity.
• Saltation: The comparatively smaller fragments of rocks are moved downstream by jumping over the floor of the river channel along with the water continuously.
• Suspension: The fine particles of the river’s load remain suspended in the river due to buoyancy of water, while they are carried downstream.
• Solution: The soluble particles are dissolved in the river water and moved downstream.

OR.
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 play an important role in the Indian monsoon system. These winds influence the onset and retreat of the monsoons in India, by seasonal shifting and creation of low presure and high presure calls respectively.

Question 2.
Classify wastes according to nature along with examples.
OR.
State three necessities of waste management.
Answer:
The different types of wastes are :

• Solid wastes: Solid wastes are any type of garbage or rubbish generated at home or outside. Eg-Food wastes newspaper, broken household or office articles, etc.
• Liquid wastes: Liquid wastes include wash waters from homes, cleaning liquids used in industries, waste waters or liquids from industries, etc. Sometimes, solid wastes are converted to liquids before discarding.
• Gaseous wastes: Gaseous wastes include CO₂, SO₂, N₂O NH₃ etc. produced as a result of manufacturing activities in industries comsumption of differnent products and other biological processes.
• Toxic wastes : Toxic wastes are harmful and hazardous poisonous wastes that threaten public health and environment. Eg-pesticides, mercury, containing equipments, lamps, batteries, etc.
• 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. Eg-domestic wastes, food left-overs, paper, glass, etc.

OR.
The necessities of proper waste management system are-

• To control different types of pollution.
• To control the spread of infectious diseases.
• To conserve environmental resources like forests, minerals, water etc.
• To reduce the amount of wastes generated everyday.
• To recycle hazardous wastes for further production of useful items.

Question 3.
Discuss three advantages each of roadways and railways in India.
OR.
State the merits of agricultural revolution as experienced in the States of Punjab and Haryana.
Answer:
The advantages of roadways in India are as follows :

• The light weight and less bulky commodity can be easily transported from one corner of the country to the other.
• A variety of vehicles, eg-buses, trucks, cycles, auto rickshaws, vans, etc. can use the same road and carry different types of commodities and number of passengers and render door-to-door services as well.
• This is the easiest mode of transport for moving raw materials to factories and finished products to markets. Hence, a large percentage of economic development of the country depends upon the roadways.

The advantages of railways in India are as follows :

• Railways transport a huge quantity of goods and passengers at a high speed and at a low cost throughout the country.
• Railways carry seeds, fertilizers, agricultural equipments to the fields and the produced crops to the markets. Railways also transport minerals, power resources, equipments etc. to the industries and their finished products to the markets. Thus railways help to bring about agricultural and industrial development in India.
• Railways help in defence of the country by transporting soldiers, ration, war equipments and other necessary things to the border regions.

OR.
The agricultural revolution experienced in the States of Punjab and Haryana is popularly known as the Green Revolution. The merits of Green Revolution are-

• Remarkable increase on production of foodcrops, especially wheat.
• Extension of agricultural land.
• Modernisation and mechanisation of agriculture.
• Reduction of past attacks due to use of better quality of insecticides and pesticides.
• Employment and improvement in the economic condition of the farmers, and thus a rise in their standard of living.
• Reduction in import of foodgrains and huge increase in the export of the same.

Question 4.
Give an account of different types of scales in tabular form as used “topographical maps”.
OR.
Distinguish between Geostationary and Sun-Synchronous satellites.
Answer:
The different types of scales used in topographical maps areas follows :

OR

Geostationary Satellites
i. The artificial satellites that orbit the earth from west to east in circular orbits in the same time as that of earth’s rotation ( 24 hours), are called geostationary satellites.	i. The sun-synchronous satellites are those which are installed on a geocentric orbit that combines altitude and inclination in such a way, that the satellite passes over any given point of the planets surface at the same local solar time.
ii. They are installed at a height of of 36,000 km approximately, above the equator.	ii. They are installed at 700-800km above the land surface and orbit the earth in circular or elliptical paths from the north polar to south polar regions.
eg : GOES-E, GOES-W, etc.	iii. eg : IRS, LANDSAT, etc.

Group-E.

(Sketches are not essential for Sightless Candidates)

1. Answer any two questions from the following :

Question 1.
Describe with sketches three landforms carved out by glacial erosion.
Answer:
The landforms curved out by glacial erosion are as follows:

i. Cirque: At the source of the glacier, the mountain wall is heavily eroded by the process of plucking and abrasion. This it looks like a scooped out huge arm chair. This is known as a cirque or a corrie. Acrque may be filled with glacier melt water and may form a cirque lake or a corrie lake.

ii. Arete: In a show-covered mountains region, two or more glaciers may originate from different slopes of the same mountain. Thus, two or more cirques may be formed or the same mountain adjecent to each other. The steep and sharp wall that separates two adjecent cirques, is known as the arete.

iii. Pyramidal peak: If a mountain has three or more aretes, it takes the structure of a pyramid, and thus is called the pyramidal peak. The tip of such a peak becomes very sharp and pointed, and is called a horn.

iv. U-shaped valley : While the glacier flows down, the intensity of side erosion is same as that of vertical or down erosion by the processes of plucking and abrasion. Hence the valley developed looks like the letter ‘U’. Thus they are called U-shaped valley.

v. Hanging valley : In a glaciated region, the main or trunk glacier cames a greater volume of ice than the tributary glaciers. Thus the main glacier has more erosive power than the smaller tributary glaciers. Hence, the main glacier forms deper valleys and the tributary glaciers form comparatively less deeper valleys. These are not visible as long as the ice cover reviews found to be hanging over the huge deep valleys. Such valleys are called hanging valley.

Question 2.
Give an account of atmospheric layers of troposphere and stratosphere.
Answer:
Troposphere

• The lowest layer of the atmosphere, lying closest to the earth is known as Troposphere.
• It extends upto 18km near the equator and 18km near the poles.
• Temperature in this layer decreases by this is known as Lapse Rate.
• About three-fourths of the total mass of the atmosphere is concentrated in this layer.
• All the weather phenomena, like wind, rainfall, storm, etc, occur in this layer.
• The upper limit of the Troposphere is known as the Tropopouse.

Stratosphere

• Stratosphere is the second layer of the atmosphere that lies above the Troposphere.
• It spreads upto 50km above the earth’s surface.
• Temperature goes on increasing in this layer at the rate of 4 for every 50km.
• A huge concentration of ozone gas is found in this layer between 20-40 km. This is also known as the Ozonosphere.
• There is very less atmospheric disturbances here. A thin layer of cirrus clouds may form at the lower layers of the stratosphere.
• Jet planes fly through this layer due to less friction due to lack of air.
• The upper limit of the stratosphere is known as stratopause.

Question 3.
Mention the location of Mediterranean climatic region and discuss its major climatic characteristics.
Answer:
Mediteranean climate is found between 30°c – 40°c latitudes in both Northern and Southern hemispheres.

• Europe: Portugal, spain, Italy, Greece
• Aisa: Western Turkey, Lebanon, Syria, Israel.
• Africa: Egypt, Morocco, Northern Algeria, Cape town.
• North America: Southern California.
• South America: Chile
• Oceania: Southern and south-western coast of Australia.

Characteristics of Mediterranean climate

• Temperature remains moderate throughout the year.
• Average summer temperature lies between 14°c 22°c
• Average winter temperature lies between 10°c -14°c
• Summers are dry and the sky remains clear during this season.
• Most of the rainfall occurs during winter.
• Average annual rainfall is 35-75cm

Question 4.
Discuss the influences of ocean currents on global climate.
Answer:
The influences of ocean currents on global climate are :
i. Control on temperature: The warm currents move towards the polar regions from the equatorial region and the cold currents flow towards the equatorial region from the polar regions. This helps in maintaining a balance between temperature of various regions due to exchange of heat.

ii. Rainfall and snowfall: The regions along which warm currents flow experience heavy rainfall. The regions along which cold currents flow, are more prone to snowfall.

iii. El Nino and La Nina: During El Nino, a warm current flows from the north towards the coast of Peru and Ecuador in South America. This causes heavy rainfall in those regions. However, India and Australia may face severe draughts. During La Nina opposite climatic conditions prevail. Australia experiences heavy rainfall, India experiences moderate rainfall and Peru and Ecuador experience draught.

2. Answer any two question from the following :

Question 1.
Explain the major factors controlling the climate of India.
Answer:
The major factors that control the climate of India are :
i. Latitude: India lies between 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, While the northern part belongs to the Temperature Zone.

ii. Relief: Temperature is inversely proportionate to altitude. 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 Himalayas: 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 sea: India has a very long coastline. The regions along the coastline enjoy moderate or maritime climate throughout the year due to the influence of the sea. Regions lying far 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 seeasonally from oposite directions. These are called monsoon winds, They have a remarkable impact on the Indian climate and economy.

vi. Western disturbances: In winter, some cyclonic winds from the Mediteranean region, called western disturbances, enter India, causing a little rainfall and snowfall in the north.

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

viii. El Nino and La Nina: During El Nino, India may experience rise in

Question 2.
Give an account of favourable physical conditions required for cultivation of tea in India.
Answer:
The favourable physical conditions required for the cultivation of tea in india are :

• Temperature: Tea can grow in temperatures between 10°c – 35°c. The best condition is 25°c  and growth is retarded below an average of 18°c.
• Rainfall: Tea requires 150-200 cm of annual rainfall well distributed throughout the year, with no long spells of dry season.
• Humidity: High humidity, heavy dews and morning fog favour rapid development of young leaves.
• Frost: Widespread winter frost is harmful for the growth of tea.
• Shade: Tea is a shade-loving plant. Hence big trees are planted in between tea plants to provide light and shade.
• Relief: Tea plants cannot tolerate stagnant of water at the base. Hence mountain slopes and undulating highlands are preferred for cultivation of tea.
• Soil: Well-drained sandy loam with porous sub-soil is favourable for tea. Virgin forest soils with good amout of iron and humus are also suitable.

Question 3.
Explain why cotton textile industry is extensively developed in Western India.
Answer:
The factors responsible for the extensive development of cotton textile industry in western india are :

• Availability of raw cotton from the black soil region of Western and Central India.
• Hot humid weather of western India helps in the growth of cotton and making of threads.
• Presence of ports at Mumbai, Kandla, Surat etc. helps in international trade.
• Availability of hydel power from Ukai, Veera, etc. thermal power from Dhubran, and atomic power from Kakrapara, Tarapore, etc.
• Good network of railways and roadways cannecting all important centres of the country.
• Availability of capital from business communitees residing in the western part of India.
• Ample labour at cheap rates.
• High demand of cotton products in the local and foreign markets.

Question 4.
Discuss the major problems of Urbanization in India.
Answer:
The major problems of urbanisation in India are :

• Unplanned growth of urban areas: Rapid concentration of population in urban areas lead to unplanned and nonsystematic growth of towns and cities,
• Accomodation: The rapidly growing population is difficult to house in the already existing urban areas, Hence, growth of slums and downtrodden areas occurs in the fringes of towns and cities.
• Availability of water: The amount of water available is not sufficient for the rapidly growing population. Hence scarcity of water occurs.
• Unemployment: A huge section of rural population comes to urban areas in search of work. But all of them do not get employment. Hence, the total percentage of unemployed population in the urban areas increases.
• Sewage and garbage disposal: The huge volume of disposable solid and liquid wastes generated by the excess population is difficult to handle with the present sewage and waste management systems. Thus waste dumping, water lagging, sewage overflow, etc. are common.

Group-F.

Locate the following with appropriate symbols and names on the given outline map of India. Attach the map with your answer paper: 1×10=10

1. Aravalli mountain.
2. River Narmada.
3. Highest rainfall receiving centre in north-east India.
4. Forest Research Institute of India.
5. A region of saline soil in eastern India.
6. A coffee producing region.
7. Rurh of India.
8. India’s largest IT industrial centre.
9. A natural port of Western India.
10. Largest megacity of Northern India.
OR
[For Sightless Candidates Only]
Answer:

6. Answer any ten of the following questions: 1×10=10

1. Name the rift valley lying between Vindhya and Satpura range.
2. Mention the name of the largest river island of India.
3. Name a coral island of India.
4. In which state of India, south-west monsoon wind strikes first?
5. Mention the name of state where mountain soils are found.
6. Which state of India ranks first in production of paddy?
7. Name one rabi crop produced in India.
8. Where in West Bengal rail engine manufacturing centre is located?
9. Name a mountain pass of Eastern Himalaya.
10. By which name, the old alluvial soil of Ganga Plain is known?
11. Name the state of India, having least population density.
12. Mention the name of the biggest port of Eastern India.
13. Which state of India ranks first in Coffee Production?
14. Name one natural port on the Eastern Coast of India.
Answer:
1. Aravalli mountain
2. River Normoda
3. Highest rainfall receiving centre in morth-east India
4. Forest research institute of India
5. A region of saline soil in eastern India.
6. A coffee producing region.
7. Rurh of India
8. India’s largest IT industrial centre.
9. A natural port of western India.
10. Largest mega city of Northern India.
OR.
[For sightless candidates only]
1. Narmoda river valley.
2 Majuli island on river Brahamaputra, Assam.
3. Lakshadweep islands.
4. Kerala
5. Sikkim, Jammu and Kashmir, Arunachal Pradesh, Assam.
6. West Bengal.
7. Wheat, barley, peas, gram, mustard, etc.
8. Chittaranjan
9. Nathula Pass, Bumla Pass
10. Bhangar
11. Arunachal Pradesh.
12. Chennai port
13. Karnataka
14. Kolkata port.

Detailed explanations in West Bengal Board Class 10 Geography Book Solutions Chapter 1.3 Works of a Glacier offer valuable context and analysis.

WBBSE Class 10 Geography Chapter 1.3 Question Answer – Works of a Glacier

Answer in short : 2 Marks

Question 1.
What is a glacier?
Answer:
A glacier is a moving body of snow and ice which under the influence of gravity moves slowly over the land downslope.

Question 2.
What is an avalanche?
Answer:
Huge amount of snow and ice breaking off and falling along steep slopes of mountains is called an avalanche.

Question 3.
Classify glaciers.
Answer:

Question 4.
What are continental glaciers?
Answer:
In higher latitudes, glaciers cover almost the whole continent due to immense cold. These are called continental glaciers. Eg. – glaciers in Antarctica, Greenland, Iceland etc.

Question 5.
What are valley glaciers?
Answer:
Glaciers that flow through mountain valleys in higher latitudes and higher altitudes are called valley glaciers. Eg-Siachen glacier in the Karakoram range.

Question 6.
What are piedmont glaciers?
Answer:
When glaciers of higher latitudes reach the foothills of mountains, they still don’t melt due to immense cold. These are called piedmont glaciers.

Question 7. a
What is an arete?
Answer:
The thin steep ridge of the mountain lying between two adjacent corries is called an arete.

Question 8.
What is a pyramid peak ?
Answer:

When three or more corries are created on the surface of the same mountain, the sharp edged landform thus created looks like a pyramid. This is called the pyramid peak.

Question 9.
What are eskers?
Answer:

Long ridge of material deposited parallel to the direction of flow of glacial melt water is called an esker.

Question 10.
What are erratics?
Answer:
When glaciers melt, the boulders get deposited in an area where they may be a total mismatch with the surroundings. These are called erratics.

Question 11.
What are outwash plains?
Answer:

Materials washed out by glacial melt water and deposited in a variety forms are called outwash plains.

Question 12.
What are kettle lakes?
Answer:
The melt water from glaciers may get accumulated in holes created in outwash plains due to melting of detached mass of ice that might have been left partly or wholly buried. These are called kettle lakes.

Question 13.
What is an iceberg ?
Answer:
The huge masses of ice floating in the oceans are called icebergs. If continental glaciers spread till the coastline, the ocean currents cause the ice at the edge of the glaciers to break and float in the water. 8/9th parts of the icebergs lie beneath the water and only 1/9th part is seen above the surface.

Question 14.
What is snowline?
Answer:
The imaginary line above which the snow never fully melts or below which line, snow starts to melt is called mountain. The height of this line varies one climatic region to another.

Question 15.
What do you know about end moraines ?
Answer:
Moraines refers to the deposition by glaciers at the foothill region. When the shape of this depositions are horse-shoe shaped and have concave slopes, they are called end moraines.

Question 16.
What is paternoster lake?
Answer:
A glacier encountering weaker rocks at its base, will be able to erode deeper than when it experiences harder, less erodable rocks. As the glacier melts, lakes form where weaker rock was excavated, this lakes are called paternoster lake.

Question 17.
What is a nunatak?
Answer:
In a continental glacier, near the edges, where the ice layers are not so thick, some hills or domes may rise above the snowy surface, which have no deposition of snow on them. These bare rocky outcrops within the glacial snow are called nunataks.

Question 18.
What are the characteristics of continental glaciers ?
Answer:
The characteristics of continental glaciers are :

1. These glaciers are larger in volume and size than other types of glaciers.
2. These glaciers are thicker at the middle and thinner at the edges. Hence they look like domes.
3. Depth of these glaciers is greater compared to other glaciers.
4. The direction of flow of continental glaciers is from the centre towards the edges from all sides.
5. The edges of these glaciers break off to form icebergs.

Question 19.
What is a snout?
Answer:
In valley glaciers, the mass of ice flows through specific valleys. The walls and base of the valley provide immense friction and try to prevent the ice from flowing. Hence, the middle part of the glacier, which experiences less friction, seem to move forward. This appears like a tongue-shaped feature. This is known as the snout of the glacier. The snow of the snouts gradually melts to give rise to rivers.

Question 20.
Why are pyramidical peaks also called ‘horns’?
Answer:
The Matterhorn peak in Switzerland is an example of a pyramid peak. Hence, following the name of the peak, the pyramidical peaks are also called horns.

Question 21.
What is boulder clay ?
Answer:
Glaciers deposit unassorted load or debris when they start melting. If big boulders get deposited over a field of sandy and clayey deposits, the landform is called boulder clay or till.

Question 22.
What do you mean by a ‘Basket of eggs’ topography ?
Answer:
When numerous drumlins are formed due to glacial deoposition very close to each other, the region looks like numerous eggs placed in a basket. Hence, such a topograhy is called a ‘Basket of eggs’ topography.

Question 23.
What is an Agamuk ?
Answer:
The huge chunks of boulders and rock fragments deposited near mountains due to depositional work of glaciers form a typical landform called Agamuk.

Question 24.
What is an ice sheet?
Answer:
An ice sheet is a large mass of ice that covers the surrounding terrain and is greater than 50,000 km². This is also known as continental glacier.

Question 25.
What is crag and tail ?
Answer:
In a glaciated region, if any huge hard block of rock lies inbetween soft rocks, the glacier erodes the softrock while climbing up the huge hard rock. The soft rocks lying at the back of the hard rock from where the glacier descends, does not get eroded much compared to the front. Thus, the huge hard rock standing out is known as the crag and the band of softrock lying at the back is known as the tail.

Question 26.
What do you mean by ice age?
Answer:
Ice age is a period of long-term reduction in the temperature of the earth’s surface and the atmosphere, resulting in the presence or expansion of continental and polar ice sheets and alpine glaciers.

Question 27.
What are neve and firn?
Answer:
Neve is a granular, porous type of snow which has been partially melted, refrozen and compacted, leading to the formation of glacial snow. This forms the surface of the upper-end of the glacier. Firn is partially compacted neve. It is a type of snow that has been left over from the past seasons and has been recrystallized into a substance denser than neve. It is intermediate between snow and glacial ice.

Answer briefly : 3 Marks

Question 1.
How is a glacier formed ?
Answer:
In higher latitudes and higher altitudes, the regions above the snowline accumulated much snow due to immense cold. This snow is gradually compacted and converted to ‘neve’. This storage of ice gradually flows down the slope of land, hence forming a glacier.

Question 2.
What is a Bergschrund ?
Answer:
A Bergschrund is a long narrow crack developed at the source of the glacier. This is created when the mass of ice tends to flow down due to gravity and the mountain walls tend to hold back the ice due to friction.

Question 3.
Mention the methods by which a glacier erodes.
Answer:
The glacier can erode by the following methods:
(a) Plucking : As the glacier starts moving, the solid mass of ice plucks out any protruding rock that comes in the way. This is called plucking.
(b) Abrasion : As the glacier moves forward, the already plucked rock fragments rolls against the floor and walls of the valley and also against each other. This makes the rock fragments rounded and smooth. This is called abrasion.
(c) Frost Wedging : When glacial ice melts partially, the water percolates into the adjacent cracks and joints. Once again when it freezes, the volume of water (as ice) increases and exerts pressure on the walls of the cracks. Thus rocks break apart. This is called frost wedging.

Question 4.
What is a fjord?
Answer:
In higher latitudes, the glaciers near sea coasts erode their valleys so deeply that the base of the valleys seem to get lowered than the sea level as well. These regions get filled up with sea water and the higher walls look like gradually submerged ridges. Such a reigion is called a fjord. Eg-‘Sogne’ fjord of Norway.

Question 5.
Why are waterfalls common in hanging valleys ?
Answer:
In mountainous regions, where the smaller glaciers meet the main glacier, the main glacier curves deeper valleys than the smaller glaciers. When the ice melts, these smaller glacier valleys seem to hang over the main glacial valley, which is quite deeper. When water flows through the hanging valleys into the main valley, they obviously form waterfalls.

Question 6.
Why is the position of the snowline flexible ?
Answer:
The presence of permanent snow varies or depends on several factors – eg. latitudes, height, slope, season, wind direction, wind speed, heat content etc. Change in any of the factors results in melting of ice or falling of new snow. Hence, the previous snow line may get changed. Thus the snowline is flexible.

Question 7.
What is a drumlin ?
Answer:
Drumlins are long narrow deposition of boulders and clay brought down by glaciers at the foot hills of the mountains. They look like inverted boats. They are also known as ‘Basket of eggs’ topography.

Question 8.
Classify moraines.
Answer:
Moraines are the depositions of rock fragments and clay brought down by glaciers and deposited along their path of movement. They can be classified as :

(a) Side moraines : When the debris is deposited along the side walls of the glacial valley, they are known as side moraines.
(b) Medial moraines : When two glaciers meet, the side moraines of both the glaciers on one side tend to merge with each other. This deposition continues for a considerable distance and lies in the middle of the newly joint glacier.
(c) End moraines : When debris is deposited at the end of the glacier after which it starts melting into water, it is known as end moraines.

Question 9.
Differentiate between Roche moutonnee and Drumlin.
Answer:

Roche moutonnee	Drumlin
i. This looks like a high heap of rocks.	i. This looks like an egg basket or inverted boat.
ii. This is an erosional landscape of glaciers.	ii. This is a depositional landscape of glaciers.
iii. The side along the flow of the glacier is smooth, while the other side is rough.	iii. The side along the flow of the glacier is rough and the other side is smooth.
iv. This may lie single.	iv. This usually lies in groups.

Question 10.
Differentiate between Continental and Mountain Glaciers.
Answer:

Continental Glaciers	Mountain Glaciers
i. This occupies huge landmasses and spreads over almost the continents.	i. This occupies mountain valleys of high altitudes and high latitudes.
ii. Largest of all glaciers.	ii. Comparatively smaller glaciers.
iii. Usually depth of ice is very high.	iii. Usually have lesser depth of ice.
iv. Eg. – Lambert in Antarctica.	iv. Eg. – Gangotri, Yamunotri etc. of the Himalaya.

Question 11.
What are crevasses?
Answer:

Crevasses are cracks formed on the surface of glaciers. If the glaciers flow over a uniform slope throughout, crevasses are not formed. But if the surface underlying the snow is rugged and undulating, the glacier has to ride the higher parts and slope down the lower parts. Thus, a great force of tension works on the snow. This creates the crevasses.

Question 12.
On what factors does the erosive power of glaciers depend?
Answer:
The erosive power of glaciers depend on the following factors :

1. Speed : If the glaciers have greater speed, they have greater rate of erosion.
2. Depth of ice : Greater the depth of ice of the glacier, greater is its erosive power.
3. Permanency of the glacier : If the glacier remains so for a long period of time, its rate of erosion will also be much greater.

Question 13.
What is ‘Snowline’?
Answer:
Snowline is the boundary that marks the existence of permanent snow beyond a certain altitude due to very cold atmospheric conditions. According to F. J. Monkhouse, snowline indicates the lowest edge of continuous snow cover.

Question 14.
Name the different landforms created by glaciers in higher altitudes.
Answer:
The landforms created by glaciers on higher altitudes are – corrie or cirque, cirque lakes, arete, pyramid peak or horn, hanging valleys, spurs, fjords etc.

Question 15.
Name the different landforms created by glaciers in lower altitudes.
Answer:
The landforms created by glaciers on lower altitudes are – roche moutonnee, crag and tail, drumlin, esker, agamuk, till, kettle, kettle lakes, outwash plains etc.

Question 16.
Differentiate between a river valley and glacial valley.
Answer:

River Valley	Glacial Valley
i. V-shaped or I-shaped valleys are formed by rivers.	i. Glaciers form U-shaped valleys.
ii. In upper course, the down cutting of valley is more than side cutting.	ii. In glacial valleys, side cutting is more compared to down cutting.
iii. The valley walls are steep and the base is narrow.	iii. The valley walls are steep and the base is broad.
iv. Valleys in most regions are called gorges and those in dry regions are called canyons.	iv. Glacial valleys are of different types, eg-Alipne, Iceland type, mixed type etc.

Answer in details : 5 Marks

Question 1.
Explain the formation of corrie, arete and pyramidal peak by glacial erosion.
Answer:

Corrie, arete and pyramidal peak are landforms formed by mountain glaciers in the higher altitudes near the source of the glaciers.
(a) Corrie or cirque : Corrie or cirque in an armchair shaped or amphitheatre or spoon shaped depression created by the glacier on the higher slopes of the mountains from where the glacier starts flowing.
(b) Arete : The steep narrow sharp ridge like landform lying between two adjacent cirques are known as arete.
(c) Pyramidal peak : If three or more glaciers descend from the same mountain, formation of cirques and arete all around give a sharp and steep look to the peak, resembling a pyramid. This is known as the pyramidal peak.

Question 2.
Describe the formation of hanging valley and Roche moutonnee.
Answer:
Hanging Valley : In high altitudes, many small glaciers may come and meet with a large or main glacier. The smaller glaciers have lesser ice content and hence lesser erosive capacity than the main glacier. Hence, the valleys curved by smaller glaciers are lesser in depth than the main glacier. When the ice melts, these smaller glacial valleys seem to hang over the main glacial valley. This kind of a landform is called a hanging valley.
i
Roche moutonnee : If any resistant rock lies in the path of a glacier, the flowing ice and rock fragments polish the surface of the resistant rock on the side in the direction of flow of the glacier. The other side of the rock is scooped, scraped and plucked by the rock fragments and ice, thus making the surface rough and rugged, as the glacier moves forward. Such a landform, resembling the ‘back of a sheep’ is called a roche moutonnee.

Question 3.
Describe some landforms formed by glacial deposition.
Answer:
The landforms formed by glacial deposition are :

i. Moraines : Any landform formed by depositions of valley and continental glaciers is called moraines. The moraines can be mainly of three types – (a) Moraines deposited along side of glacial valley floor are called lateral moraines. (b) Where two lateral moraines of adjacent glaciers combine, the deposition lying in the middle of the main glacier is called medial
moraine. (c) Moraines deposited at the end of a glacier are called terminal or end moraines.

ii. Eskers : Long ridges of material deposited parallel to the direction of the flow of glacial melt water are called eskers.

iii. Erratics : These are depositions of boulders and rock fragments in an area where they are a total mismatch with the surroundings.

iv. Drumlins : These are low elongated hills formed by glacial deposits. They are also called ‘Basket of eggs’ topography.
v. Kames: These are small rounded hillocks of sand and gravel.
vi. Outwash plains : These are materials

Question 4.
Compare and contrast between the works of river and glacier.
Answer:

Item	Works of river	Works of glacier
(i) Definition	A flowing body of water coming downslope from high lands to lowlands due to gravity, meeting any sea, ocean, lake etc. is called a river.	A flowing body of huge amount of ice coming downslope from a mountainous region due to gravity is called a glacier.
(ii) Speed	Rivers have great speed in the mountainous region, medium speed in plateau region and less speed in the plains.	Glaciers have yery low speed throughout the course.
(iii) Path	River finds its path avoiding any obstacle by taking curves.	Glacier tends to flow in a straight path removing any obstacle that comes in the way.
(iv) Working capacity	Depends on slope of land, quality of rocks in the channel and water content.	Depends on amount of ice, slope of land and quality of rocks in the channel.
(v) Works	Erosion, transportation and deposition.	Erosion, transportation and deposition.
(vi) Methods of erosion	Hydraulic action, corrasion or abrasion, attrition, solution.	Plucking, abrasion and frost wedging.
(vii) Type of erosion	Mechanical and chemical	Only mechanical
(viii) Valley	V-shaped	U-shaped.
(ix) Erosional landforms	Gorge, canyon, waterfalls, pot hole, plunge pool, interlocking spur etc.	Corrie, arete, pyramid peak, hanging valley, roche moutonnee, crag and tail etc.
(x) Depositional landforms	Alluvial fan and cone, flood plain, natural levee, delta, sand bar, braided channel etc.	Moraines, eskers, kames, drumlin, erratics, outwash plains etc.

Multiple Choice Question (MCQ) :

Question 1.
Which of these regions has continental glaciers ?
(A) Himalaya
(B) Alps
(C) Andes
(D) Greenland
Answer :
(D) Greenland

Question 2.
Which landform is created by glacial erosion ?
(A) Arete
(B) Moraine
(C) Drumlin
(D) Plunge pool
Answer :
(A) Arete

Question 3.
Which landform is created by glacial deposition ?
(A) Cirque
(B) Hanging Valley
(C) Arete
(D) Moraine
Answer :
(D) Moraine

Question 4.
Cirques are
(A) Basins formed by river erosion
(B) Basins formed by wind erosion
(C) Vast amphitheatre like basin curved by glaciers
(D) None of these
Answer :
(C) Vast amphitheatre like basin curved by glaciers

Question 5.
Kettle holes are
(A) Depressions made by melting ice
(C) Depressions made by wind
(B) Depressions found at foot hills
(D) None of these
Answer :
(A) Depressions made by melting ice

Question 6.
Horn is created by
(A) One cirque
(B) Two cirques
(C) Cols
(D) Aretes
Answer :
(D) Aretes

Question 7.
Moraines are
(A) Depositions by rivers
(B) Depositions by glaciers
(C) Depositions by winds
(D) None of these
Answer :
(B) Depositions by glaciers

Question 8.
Drumlines are
(A) Boat-shaped depositions
(B) Narrow vallys
(C) Armchair shaped depression
(D) Pyramid peak
Answer :
(A) Boat-shaped depositions

Question 9.
Kames are
(A) Rift valleys
(B) Sand dunes
(C) Steep hills
(D) Long irregular hills formed by glacial deposition
Answer :
(D) Long irregular hills formed by glacial deposition

Question 10.
Outwash plain is
(A) Debris deposited by river
(B) Formed by silt deposition
(C) Debris deposited by ice at valley bottom
(D) None of these
Answer :
(C) Debris deposited by ice at valley bottom

Question 11.
Which landform is created by glacier?
(A) Inselberg
(B) Meander
(C) Pyramidal peak
(D) Gour
Answer :
(C) Pyramidal peak

Question 12.
Basket of eggs topography is related with
(A) Eskers
(B) Drumlins
(C) Outwash plains
(D) Corrie
Answer :
(B) Drumlins

Question 13.
Fjord coast is formed by
(A) Action of sea waves
(B) Submergence of river valleys
(C) Submergence of glacial valleys
(D) Action of wind
Answer :
(C) Submergence of glacial valleys

Question 14.
Hanging Valleys are formed by
(A) Mountain glaciers
(B) Continental glaciers
(C) Piedmont glaciers
(D) Coastal glaciers
Answer :
(A) Mountain glaciers

Question 15.
Glacial valley is
(A) I-shaped
(B) U-shaped
(C) V-shaped
(D) Y-shaped
Answer :
(B) U-shaped

Question 16.
The altitude over which snow never melts is called
(A) Snowline
(B) Glacier
(C) Tree line
(D) Cold wall
Answer :
(A) Snowline

Question 17.
Who commented – ‘A glacier is a mass of snow and ice that moves slowly over the land away from its placeof accumulation?
(A) Worcester
(B) Flint
(C) Lobeck
(D) Thombry
Answer :
(A) Worcester

Question 18.
The biggest glaciers on the earth’s surface are called
(A) Continental glaciers
(B) Cirque glaciers
(C) Niche glaciers
(D) Ice sheets
Answer :
(D) Ice sheets

Question 19.
Antarctica and greenland ice sheets are the examples of
(A) Mountain or valley glaciers
(B) Piedmont glaciers
(C) Continental glaciers
(D) Ice shelf
Answer :
(C) Continental glaciers

Question 20.
Which of the following is a floating thick ice sheet or ice cap attached to the coast?
(A) Ice field
(B) Ice shelf
(C) Valley glacier
(D) Cirque glacier
Answer :
(B) Ice shelf

Question 21.
The destruction of glacier front due to melting of ice consequently due to increase of temperature is called
(A) Advancement of glacier
(B) Stagnation of glacier
(C) Ablation of glacier
(D) None of these
Answer :
(C) Ablation of glacier

Question 22.
The glacier erodes its bed and side walls with the help of tools of erosion by the mechanism of
(A) Attrition
(B) Abrasion
(C) Corrosion
(D) Plucking
Answer :
(B) Abrasion

Question 23.
‘Head wall’ is a component of
(A) Tarn
(B) Nunatak
(C) U-shaped valley
(D) Cirque
Answer :
(D) Cirque

Question 24.
‘Corrie’ is the name of _____ in Scotland.
(A) U-shaped valley
(B) Arete
(C) Horn
(D) Cirque
Answer :
(D) Cirque

Question 25.
The line above which snow never meets in the high altitudes is called
(A) Snow line
(B) Glacier
(C) Iceberg
(D) Blow out
Answer :
(A) Snow line

Question 26.
______ part of an iceberg floats above the water surface
(A) 8 / 9
(B) 2 / 9
(C) 1 / 9
(D) 9
Answer :
(C) 1 / 9

Question 27.
Continental glaciers are seen is
(A) Himalayas
(B) Alps
(C) Andes
(D) Antarctica
Answer :
(D) Antarctica

Question 28.
The landform between two adjacent cirques is called
(A) Roches moutonnee
(B) Arets
(C) Pyramid peak
(D) Eskar
Answer :
(B) Arets

Question 29.
_____ is an example of an pyramidal peak
(A) Mont Blanc
(B) Matterhorn
(C) Mt. Abu
(D) Kanchenjunga
Answer :
(B) Matterhorn

Question 30.
The deepest fjord of the world is
(A) Dry galski fjord
(B) Geiranger fjord
(C) Soque fjord
(D) King oscar fjord
Answer :
(C) Soque fjord

Question 31.
Deep cracks on the surface of the mountain glacier are called
(A) Nunatak
(B) Creavasse
(C) Arete
(D) Cirque
Answer :
(B) Creavasse

Question 32.
A pyramidical peak formed due to recession and intersection of three or more cirques is called
(A) Horn
(B) Col
(C) Nunatak
(D) Arete
Answer :
(A) Horn

Question 33.
The higher peaks and mounds surrounded by ice from all sides are called
(A) Arete
(B) Nunatak
(C) Cirque
(D) Hom
Answer :
(B) Nunatak

Question 34.
Which glacial landform is formed by abrasion and plucking of step faults?
(A) Nunatak
(B) Roche Moutonne
(C) Grag and tail
(D) Glacial stairways
Answer :
(D) Glacial stairways

Question 35.
The rock debris carried by the glaciers are collectively called
(A) Tills
(B) Avalanches
(C) Glacial drifts
(D) Moraines
Answer :
(C) Glacial drifts

Question 36.
Which of the following terms refer to the depositional landforms of direct glacial origin?
(A) Moraines
(B) Talus
(C) Rock waste
(D) Regolith
Answer :
(A) Moraines

Question 37.
Which of the following are depressions in the outwash plains ?
(A) Kettles
(B) Cone Kames
(C) Beaded eskers
(D) Hummocks
Answer :
(A) Kettles

Question 38.
A tributary valley associated with the main glacial valley is called a
(A) Hanging valley
(B) V-shaped valley
(C) U-shaped valley
(D) None of these
Answer :
(A) Hanging valley

Question 39.
An armchain type of hollow cut into the mountain by a moving glacier is called a ______.
(A) U-shaped valley
(B) Roche moutonne
(C) Cirque
(D) Glacier lake
Answer :
(C) Cirque

Question 40.
Glacial troughs occupied by the sea are called
(A) Fjords
(B) Glacial groones
(C) Finger lakes
(D) None of these
Answer :
(A) Fjords

Question 41.
Fjord coasts are common in
(A) Norway
(B) Germany
(C) Sweden
(D) France
Answer :
(A) Norway

Fill in the blanks : 1 Mark

1. Glaciers flow faster in the ________ season.
2. The German word ‘berg’ means _______.
3. Bergschrunds are known as _______ in French.
4. The rock fragments of different sizes coming down by the melting of the glaciers is called _______.
5. The longest glacier of India is _______.
6. The Peterman glacier of greenland is a _______ glacier.
7. The ice line or snow line lies at the highest altitude in the _________ region.
8. The largest continental glacier of the word is the ______ glacier.
9. ________ is known as the land of fjords.
10. Corrie lakes are known as ______ in France.
11. The snow-less peaks in an ice covered regions are called _______.
12. Drumlins looks like _______.
13. The limit below which snow starts melting is called _______.
14. Eskar is a ________ landform formed by glacier.
15. Horizontal and parallel cracks or fractures found on the surface of a glacier are called _______.
Answer :
1. Summer
2. mountain
3. Rimaye
4. Boulder clay
5. Siachen
6. Continental
7. Equatorial
8. Lambort
9. Norway
10. Cirques
11. Nunatakes
12. inverted boats
13. snowline
14. Depositional
15. Crevasse

State True or False : 1 Mark

1. The period between two ice ages is called the non-ice age. [ ]
2. The outwash plain separated by a river is called the valley train. [ ]
3. Presently, the largest number of glaciers are found in Asia. [ ]
4. Eskers are formed by erosional work of glaciers. [ ]
5. Glaciers do not lie at the same altitude always. [ ]
6. The glacial valleys are U-shaped. [ ]
7. The floating blocks of ice in oceans are called snow lines. [ ]
8. The tongue-shaped part in front of a moving glacier is called a shout. [ ]
9. Matterhorn peak in the Alps is a pyramidical peak. [ ]
10. Small continental glaciers are known as glacier sheets. [ ]
11. Nunatakes are seen in polar region. [ ]
12. The submerged glacial valleys formed due to erosion by continental or mountain glaciers are called fjords. [ ]
13. The regions clustered with drumlines is also called ‘basket of eggs topagraphy’. [ ]
14. Waterfalls are formed from the meltwater of hanging valleys after deglaciation. [ ]
15. Altitude of snowline varies with latitudes. [ ]
Answer:
1. True
2. True
3. False
4. False
5. True
6. True
7. False
8. True
9. True
10. False
11. True
12. True
13. True
14. True
15. True

Answer in few words : 1 Mark

Question 1.
What is a crevasse?
Answer:
Cracks that develop on the surface of a glacier.

Question 2.
What is snow line?
Answer:
The altitude above which there is permanent snow lying throughout the year is known as the snow line.

Question 3.
What is a glacier?
Answer:
A glacier is a body of ice that flows downwards along the slope of the land due to gravity.

Question 4.
What is a snout ?
Answer:
The glacier’s downstream end is called snout.

Question 5.
What is iceberg ?
Answer:
Huge blocks of ice that break off from glaciers and fall into the sea are called icebergs.

Question 6.
Where do piedmont glaciers lie ?
Answer:
At the foot of the mountains.

Question 7.
Which is the world’s longest continental glacier ?
Answer:
Lambert glacier in Antarctica.

Question 8.
What are the main works of a glacier?
Answer:
Erosion, transportation and deposition.

Question 9.
How are moraines formed ?
Answer:
By glacial deposition.

Question 10.
What are kames?
Answer:
Rounded hillocks of sand and gravel formed due to glacial deposition.

Question 11.
How does a landform comprising of several drumlins look like?
Answer:
Basket of eggs topography.

Question 12.
What kind of a glacier is Siachen in India ?
Answer:
Mountain or valley glacier.

Question 13.
What are compaction of granular snow called ?
Answer:
Firm.

Question 14.
Which continent has the maximum number of glaciers ?
Answer:
Antarctica.

Question 15.
Name the largest valley glacier of the world ?
Answer:
Lambert.

Detailed explanations in West Bengal Board Class 10 Geography Book Solutions Chapter 1.2 Works of a River offer valuable context and analysis.

WBBSE Class 10 Geography Chapter 1.2 Question Answer – Works of a River

Answer in short : 2 Marks

Question 1.
What is the hydrological cycle?
Answer:
Water is present on the surface of the earth in rivers, lakes, oceans, ponds and other water bodies. This water gets evaporated by the sun’s heat and mixes with the atmosphere. Again, this vapour condenses and forms clouds and comes back to the earth’s surface as rain or snow. This cyclical movement of water from the earth’s surface and sub-surface to the atmosphere and vice versa is known as the hydrological cycle.

Question 2.
What is tributaries and distributeries ? Give example.
Answer:
Tributary : A tributary is a stream or a river which flows into a larger river. A tributary does not flow directly into a sea or ocean. For example, river Gomati and Son are tributaries of river Ganga.
Distributary : A stream that flows into a main-stream (or parent) river called distributary. For example, Hooghly is the distributary of Ganga.

Question 3.
What is peneplain?
Answer:
A more or less level land surface produced by erosion over a long period of time is called peneplain. It is a representation of a near-final stage of fluvial erosion. e.g.-Chotonagpur region.

Question 4.
What is Knick point ?
Answer:
Knick point refers to a particular point of the surface. where there is a sharp change in the slope of a river. After rejuvination, this particular point of sharp change of river slope occured, which is known as knick point.

Question 5.
What do you mean by rejuvination?
Answer:
The action of restoring a river or stream to a condition characteristic of a younger landscape is called rejuvination. Rejuvination occured for various reasons, i.e. earthquake, river captured etc.

Question 6.
What is a river ?
Answer:
A river is a flowing water body, which collects its water from rain and snow melt, flows down the hilly slopes through a natural channel due to gravitational force and meet with any other water body like ocean, sea, lake etc.

Question 7.
What is a river basin ?
Answer:
The area drained by the main river, the tributaries and distributaries from the source to the mouth is called the river basin.

Question 8.
What is a water-divide?

Answer:
The highland that separates two or more river basins lying adjacent to each other is called a water-divide. Usually the hills, mountains, ridges etc. act as waterdivides.

Question 9.
What is a river valley ?

Answer:
The channel through which a river flows, is known as the river valley. The shape and size of the river valley depends on the amount of water, depth of water and speed of the river.

Question 10.
What is an ideal river?
Answer:
An ideal river is one which has three prominent courses from source to mouth, i.e.- upper course or youth stage, middle course or maturity stage and lower course or old age stage.

Question 11.
Why is river Ganga known as an ideal river ?
Answer:
River Ganga is known as an ideal river because it exhibits all the three stages of a river. (i) The upper course lies from Gomukh to Haridwar, (ii) The middle course lies from Haridwar to Dhulian in West Bengal, (iii) The lower course lies from Dhulian to Gangasagar in West Bengal.

Question 12.
What is ‘Sixth power law’?
Answer:
The transportation capacity of a river depends on the river’s velocity and volume of water. If the velocity of the river is doubled, the transportation capacity is increased by 2⁶ = 64 times. This is known as the ‘Sixth power law’ of a river.

Question 13.
Name the methods by which a river erodes.
Answer:
A river erodes by the methods of – hydraulic action, corrosion or abrasion, attrition and solution.

Question 14.
Name the methods by which a river transports the eroded material.
Answer:
A river transports the eroded materials by – traction, saltation, suspension and solution processes.

Question 15.
Mention the factors on which the transportation capacity of a river depends.
Answer:
The transportation capacity of a river depends on – slope of the river valley, velocity of the river, volume of water, size, shape and characteristics of the loadbeing carried.

Question 16.
What is a pot hole ?

Answer:
The round pot-like holes cut on the river beds by the swirling water and the rock fragments by the process of corrosion or abrasion are called potholes.

Question 17.
What is a plunge pool ?
Answer:
The depression or hole created at the foot of a waterfall due to falling of water along with rock fragments with high velocity, is known as a plunge pool.

Question 18.
What is a cataract?
Answer:
When a series of waterfalls come down in steps over a staircase-like land form, it is known as a cataract.

Question 19.
What is a cascade?
Answer:
A series of small waterfalls of the same river lying close to each other is called a cascade.

Question 20.
What is a rapid ?
Answer:
When small streams or waterfalls come down with high velocity by jumping step by step over the area, it is called a rapid.

Question 21.
Name the different types of deltas.
Answer:
The different types of deltas are : Bird’s foot delta, Arcuate delta and Cuspate delta.

Question 22.
Give a brief introduction of the New Moore island.
Answer:
The newly formed island at the Indo-Bangladesh border, five kmsouth from the mouth of River Hariyabhanga in the Bay of Bengal, is known as the “New Moore’ or ‘Purbasha’ island.

Question 23.
What is a catchment area or catchment basin ?
Answer:
In the hilly regions, numerous small streams and springs of water flow from different directions and contribute the water to form a main river. These numerous thin streams and springs help to keep the supply of water continuously for the main river. This region, from the main river takes shape of a basin is called the catchment area or catchment basin.

Question 24.
What do you mea by ‘River regime’ ?
Answer:
According to F. J. Monkhouse, river regime refers to the seasonal variation of water volume in the river.

Question 25.
Mention the works done by a river in its course of flow.
Answer:
An ideal river has three stages in its course of flow. In the upper course, the river mainly erodes materials. In the middle course, the main work is transportation of the eroded load. In the lower course, the main work is deposition of the load transported so far.

Question 26.
What is ‘Cusec’ and ‘Cumec’?
Answer:
‘Cusec’ and ‘Cumec’ are units of measuring the volume of water flowing through a river. ‘Cusec’ refers to the amount of cubic feet of water flowing through a particular point of the river in one second time. ‘Cumec’ refers to the amount of cubic metres of water flowing through a particular point of the river in one second time.

Question 27.
What do you mean by the last limit of erosion of a river ?
Answer:
Last limit of erosion of a river refers to the last limit of the lower course of the river where its erosive power finally ends. Usually, the sea level is considered as the last limit of erosion of a river.

Question 28.
What do you mean by degradation by river ?
Answer:
In a river, if the load is lesser than the capacity of load that it can carry, it continues its work of erosion, thus lowering the river beds and widening the walls. This is known as degradation by river.

Question 29.
What do you mean by aggradation by river ?
Answer:
In a river, if the load is far more than the capacity of load that it can carry, it starts depositing the load, thus increasing the height of landforms and decreasing the depth of the river beds. This is known as the aggradation of river.

Question 30.
Name some important water-divides in India.
Answer:
The important water-divides present in India are :

1. The Himalayan range (the largest water-divide of India)
2. The Western Ghats (the second largest water-divide of India)
3. The Vindhya and Mahakal ranges (the third largest water-divide of India)
4. The Satpura range.

Question 31.
What is a ‘Fall line’?
Answer:
In a hilly region or a plateau region, when numerous small rivers flow towards a steep and almost vertical edge of a mountain ridge or plateau, a number of waterfalls are created in a line. This is known as a ‘Fall line’. Eg. – In North America, the Appalacian mountains meet the coastal plains in a steep slope, creating a series of waterfalls along the edge of the range.

Question 32.
Name the landforms created in the upper course of a river.
Answer:
The different landforms created in the upper course of a river are – V-shaped valleys, U-shaped valleys, gorges, canyons, waterfalls, plunge pools, pot holes, interlocking spurs etc.

Question 33.
Name the landforms created by deposition of rivers.
Answer:
The different landforms created in the lower course of a river are – alluvial cone, alluvial fan, flood plain, natural levee, meanders, sandbars, delta etc.

Question 34.
What is an arcuate delta?
Answer:
The deltas whose outer boundary lies in an arch or looks bow-shaped towards the sea are called arcuate deltas. Eg.- deltas of rivers Ganga, Nile, Hwang Ho etc.

Question 35.
What is a bird’s foot delta ?
Answer:

The deltas that look like a bird’s claws or fingers spreading one beside the other, are called Bird’s foot deltas. Eg. delta of river Mississippi in North America.

Question 36.
is a cuspate delta ?
Answer:

The deltas which have sharp edges towards the sea, and look like cusps or pointed teeth pointing towards the sea at the edge, are called cuspate deltas. Eg-deltas of rivers Tiber in Italy and Ebro in Spain.

Answer in brief : 3 Marks

Question 1.
When does a river start depositing its load ?
Answer:
The river starts depositing its load under the following conditions :
(a) If the volume of water in the river reduces due to less rainfall, drought, dry season or percolation through rock beds,
(b) If the slope of the river valley reduces, it also reduces the speed of the river.
(c) If load of the river increases.
(d) If the river flows through a lake for a certain length.

Question 2.
Differentiate between abrasion and attrition.
Answer:

Abrasion	Attrition
i. The river beds and walls get eroded by action of rock fragments hitting against them.	i. The rock fragments carried by the river hit against each other and reduce in size.
ii. Rock fragments collide against river beds and walls.	ii. Rock fragments collide against each other.
iii. This type of erosion is very effective.	iii. This type of erosion is less effective.
iv. This type of erosion creates pot holes, plunge pools etc.	iv. This type of erosion creates sand, silt, clay etc.
v. Depth and width of river channels increase.	v. Depth of river channel is reduced by certain deposition of silt or sand.
vi. Abrasion does not hinder transportation of materials by rivers.	vi. Attrition hinders transportation of materials to a certain extent.

Question 3.
Why are V-shaped valleys created in the upper course of rivers?
Answer:
The causes of formation of V-shaped valleys in the upper course of rivers are:

(a) The rivers have high velocity in the upper course. They cut downwards much more than sidewards. Thus the valleys look like a ‘V’.
(b) Sometimes the ‘I’ shaped valleys may collapse to form ‘V’ shaped valleys.
(c) The hard rocks of the river valley walls are difficult to erode by sidewise pressure of water than downward pressure.

Question 4.
Why is erosion predominant in the upper course of a river?
Answer:
Erosion is predominant in the upper course of a river as – (a) Steep slope of the region gives high velocity to the river and increases its erosive powers. (b) Volume of water remains high due to snow melt as well as rain water, which makes the river more active.

Question 5.
Differentiate between ‘Gorge’ and ‘Canyon’.
Answer:

Gorge	Canyon
i. Very narrow and deep valley created in hard rock mountainous regions.	i. Very narrow and deep valley created in soft rock arid and semiarid mountainous regions.
ii. Formed by down cutting of river much more compared to side cutting.	ii. Formed by down cutting of perennial rivers in arid regions, where side cutting is prevented due to lack of rainfall.
iii. Found in wet high fold mountain regions.	iii. Found in dry and arid regions and limestone regions as well.
iv. Resembles the alphabet ‘V’.	iv. Resembles the alphabet ‘I’
v. Eg. – Royal Gorge of Arkansas, Sampo Gorge of Tibet.	v. Eg. – Grand Canyon of the river Colorado, USA is the deepest canyon of the world.

Question 6.
Mention the conditions where a waterfall can be created.
Answer:
Water of a river falling freely from a certain height in the upper course of the river is called a waterfall. Waterfalls can be created by the following conditions:
(a) Hard and soft rock beds lying alternately horizontal, vertical or diagonal to each other.
(b) If a plateau meets a plain in a steep slope.
(c) Faulting across the river valley.
(d) Hanging valleys created by glacial action.
(e) Knick points created due to rejuvination of rivers.

Question 7.
Differentiate between alluvial cone and alluvial fan.
Answer:

Alluvial cone	Alluvial fan
i. When the river leaves the mountainous region and enters a region of less slope suddenly, it deposits its load like pebbles, sand, rock fragments etc. in the form of a cone. This is called an alluvial cone.	i. When water flows over the alluvial cones, the depositions of the cones get spread and looks like a halfcircle. This is known as an alluvial fan.
ii. This looks like a cone.	ii. This looks like a half-circle or a hand fan.
iii. Height of the cone is greater than the alluvial fan.	iii. Height of the fan is lower than the alluvial cone.
iv. Slope is steep.	iv. Slope is gentle.

Question 8.
Discuss briefly the different processes of transportation of load by a river.
Answer:
A river transports its load by the following processes:
(a) Traction : The heavier and large rock fragments are forced to flow down
along the river water by rolling on the floor of the river channel due to gravity.
(b) Saltation : The fragments of rocks are moved downstream by jumping over the river bed continuously.
(c) Suspension : The fine particles of the river’s load remain suspended in the river due to buoyancy of water while they are carried downstream.
(d) Solution : Soluble particles are dissolved in the river water and moved downstream.

Question 9.
What is a flood plain ?
Answer:

In the lower course, the speed of the river is much less due to very gentle slope of the land. The river starts depositing its load in the river bed itself, thus reducing its water holding capacity. During the rainy season, when excess water comes into the river, it overflows. Much of silt, sand and clay deposits also overflow with the water and spread over large areas. This process of repeated overflow and spread of silt develops an extensive plain on both sides of the river, known as flood plains.

Question 10.
What is a natural levee?
Answer:
When silt, clay etc, are deposited at the banks of a river in the middle course every year, the height of the banks are increased compared to the adjacent lands. This looks like a natural dam, and is known as a natural levee. Such features on either side of the river channel helps to increase the depth of the river bed and its water holding capacity.

Question 11.
Differentiate between the Catchment Area and River Basin.
Answer:

Catchment Area	River Basin
i. At the source of a river, numerous small streams and springs of water flow downwards from the surrounding highlands to supply water to the main river. This is known as the catchment area.	i. The main region through which the main river, tributaries and distributaries flow is known as the river basin.
ii. Main function of the catchment area is to supply water to the main river.	ii. Main function of the river basin is to collect water from rainfall and other tributaries and make it flow towards the sea.
iii. Catchment area lies only at the source of the river.	iii. River basin spreads after the catchment area till the mouth of the river.
iv. Catchment area is much smaller compared to the basin of the same river.	iv. River basin is many times larger than its own catchment area.

Question 12.
By what processes does the river erode in its course of flow ?
Answer:
A river erodes in the course of its flow by the following processes :

1. Hydraulic action : This is the process by which the river water itself exerts pressure and friction and causes erosion.
2. Corrosion : In this process the rock fragments and pebbles collide against the walls and floor of the river basin and cause erosion.
3. Attrition : The rock fragments and pebbles flowing in the river collide against each other and break into smaller fragments.
4. Cavitation : In a turbulent stream, numerous air bubbles are created. These bubbles exert severe pressure when they burst, thus can cause erosion.
5. Solution : Soluble materials may get dissolved in river water and get removed. This causes erosion.

Question 13.
On what factors does the transportation capacity of a river depend ?
Answer:
The transportation capacity of a river depends on the following factors :

1. Slope of land: Greater the slope of land, greater will be the velocity of the river, hence, greater will be the capacity of transportation.
2. Amount of water : Greater the amount of water, greater is the transporting capacity of a river.
3. Amount of load : Greater the amount of load, lesser is the transportation capacity.
4. Size and weight of load: Greater the size and weight of load, lesser is the transportation capacity.

Question 14.
On what factors does the erosive power of rivers depend?
Answer:
The erosive power of the rivers depend on the following factors :

1. Speed of the river: The speed of the river depends on the slope of the land. Higher the speed, greater the erosive capacity of the river.
2. Amount of water : Greater the amount of water present in a river, greater is its erosive power. It can be noted that in rainy seasons, when the water level of the rivers increases, their erosive powers also increase.
3. Nature of rocks in river bed : If the rocks of the river bed are soft in nature, the river will erode more. If the rocks are hard, erosion will be less.
4. River load: The amount of load carried by the river also influences erosive power of the river. Greater the amount of load, greater is the amount of erosion.

Question 15.
How are pot holes formed ?
Answer:

The river bed is much eroded by the rock fragments and pebbles being carried by the river itself. When these rock fragments hit constantly against the river bed, the softer rocks get eroded away, creating hollows or depressions. When water falls into these depressions, they swirl around and then move forward. These shallow depressions or hollows are called pot holes.

Question 16.
What is a meander?
Answer:

In the course of flow of a river, the speed of the river is much reduced from the middle course towards the lower course. This reduces the carrying capacity of the river. The river starts depositing materials within its own bed as well as the banks. Thus obstructions are created in the course of flow. To avoid these obstructions, the river starts taking curves gradually and elongates its course, so that all can be accommodated. These curved portions of the river are called meanders. Meanders may get intensely curved and cut off to form ox-bow lakes.

Question 17.
What is an ox-bow lake?
Answer:

In the middle and lower course of a river, the speed of the river reduces so much that the carrying capacity of the river also reduces. It starts depositing materials within its own bed as well as on the banks. Thus, the river starts taking curves, forming meanders. When these meanders take intense curves, they may get cut off from the main river due to depositions that block their way. The main river flows by in a straight path and the cut-off part remains stagnant, forming a lake. These lakes look like the foot of a horse or an ox. Hence, they are called ox-bow lakes.

Question 18.
What do you mean by river capture?
Answer:
When two streams are flow along a water divide, the stronger stream erodes faster and greater with the passage of time, the headward erosion of the stronger stream erode the water divider and flows instead down the bed of neighbouring weaker stream. This phenomena is called river capture. This can happen for several reasons, including earth movement, landslide or ice sheet sliding etc.

Question 19.
Classify deltas according to their origin and explain them.
Answer:
There are two types of deltas according to their origin, such as (A) Constructive and (B) Destructive deltas.
(A) Constructive delta : Rivers deposited all eroded materials (sand, silt etc) into its beds in the lower course and form triangled new land called delta. These deltas are also called constructive delta. Such as Majuli.
(B) Destructive delta : When these deltas are continuously changing their shape and size for the action of waves, and tides, they are called desctructive delta. Such as deltas of river Rhone

Question 20.
Why do floods occure frequently in the lower course of the river?
Answer:
Lower course of the rivers are prone to frequent floods. The reasons behind this are :
i. Surface slope is almost zero in the lower course of the river. So huge amount of water of the river can not able to flow with high velocity towards the sea.
ii. River beds are loaded with maximum deposits. Thus the depth of the river channel gradually decreases. During the rainy season, as the extra amount of water is added to the river, both the banks of the river get flooded.

Answer in details : 5 Marks

Question 1.
Describe the landforms created by erosion of river in the upper course.
Answer:
The various landforms formed in the upper course of the river are :

(a) Gorge or V-shaped valley : In the upper course, the down cutting force of the river is much more than lateral erosion. Hence, the channel develops more depth than width, and looks like a ‘V ‘ shaped valley.
(b) Canyan or I-shaped valley : When the river flows through an arid region made up of non-resistant rocks, most of its energy is spent in down-cutting rather than widening of the valley. Thus the valley developed looks like ‘I’ shaped.
(c) Pot holes : Round disc-like depressions curved by the swirling water and rock fragments on the bed or floor of the river are called pot holes.

(d) Waterfalls : When water of the river falls freely from a height due to very steep slope, it is called a waterfall. They are further classified into rapids, cataracts and cascades.

(e) Interlocking spurs : When a number of projecting ridges or spurs extend from opposite sides of the wall of a V-shaped valley alternately, they seem to overlap or interlock. Such a series of spurs are called interlocking spurs.

Question 2.
Discuss the landforms formed due to deposition in the middle course of a river.
Answer:

The landforms formed in the middle course of a river are :
(a) Alluvial cone : As the river descends from a mountain and enters into a plain, it deposits extra load at the foothills in the form of a cone. This is known as alluvial cone.
(b) Alluvial fan : When the alluvial cone spreads wider and looks like a half-wide or a hand fan, it is known as the alluvial fan.
(c) Flood plains : Flooding of the rivers spread silt and clay to extensive areas on both sides of the river channel. This forms the flood plains.

(d) Natural levee : Repeated flooding tends to increase the height of the river banks and looks like long extensive dams along the banks. This is called natural levee.
(e) Meanders : The river develops broad bends and ‘S’ curves while flowing through the depositions in the middle course. These are called meanders.

(f) Ox-bow lakes: When the curves of the meander comes too close, the loop tends to join, forming a neck. The curved portion of the loop is gradually cut-off by further deposition. This horse-shoe shaped stagnant water body is known as the ox-bow lake.

Question 3.
What is a delta ? Why do deltas develop at the mouth of the rivers?
Answer:
Velocity of the river is almost nil where it meets with the sea. Thus, the heaviest amount of depositions occur here. The main channel is broken into numerous distributaries as more and more depositions take place. The region acquires a triangular shape and looks like the Greek letter Delta (Δ), hence the name. Deltas develop under the following conditions :

(a) The sea bed near the mouth of the river is very shallow.
(b) Slope is negligible.
(c) Tidal action is low.
(d) Huge amount of bed load.
(e) Numerous tributaries of the main river to add up to the load.
(f) Low current of river water at the mouth.
(g) Wind blowing in opposite direction to the flow of river water.
(h) Enclosed sea with lesser disturbances.
(i) Long course of the river.
(j) Absence of lakes and other depressions in the path of the river.
(k) Wet and humid weather rather than dry weather.

Question 4.
Compare and contrast alluvial cone with delta.
Answer:

Alluvial cone	Delta
i. Formed due to deposition of materials at the foot hills of mountains when the river enters the plains from the mountains.	i. Formed due to heavy deposition of materials when the river tends to meet the sea at the lower course.
ii. Formed of coarse and bigger rock fragments deposited at the foot hills.	ii. Formed of very fine silt and clay particles deposited at the mouth of the river.
iii. Resembles a cone.	iii. Resembles a flat triangle area.
iv. Covers a smaller area.	iv. Covers a larger area.
v. No other classification.	v. Can be classified into bird’s foot, arcuate and cuspate deltas.

Multiple Choice Questions (MCQ) : 1 Mark

Question 1.
A river is a part of the – cycle.
(A) Hydrological
(B) Biological
(C) Ecological
(D) Atmosphere
Answer:
(A) Hydrological

Question 2.
The river attains water from
(A) Rainfall
(B) Snow melt
(C) Rain and show melt
(D) None of these
Answer:
(C) Rain and show melt

Question 3.
Qarrying and removing of loose bedrocks by running water of a river is known as
(A) Corrosion
(B) Hydraulic action
(C) Solution
(D) Attrition
Answer:
(B) Hydraulic action

Question 4.
The process of erosion by collision between flowing rocks and the river bed and walls is called
(A) Corrosion
(B) Traction
(C) Solution
(D) Attrition
Answer:
(A) Corrosion

Question 5.
Erosion of materials by dissolving in river water is called
(A) Abrasion
(B) Attrition
(C) Solution
(D) Saltation
Answer:
(C) Solution

Question 6.
Wearing down of rock materials by collision against each other is known as
(A) Attrition
(B) Solution
(C) Transportation
(D) Saltation
Answer:
(A) Attrition

Question 7.
Large rocks and pebbles are dragged by the river by the process of
(A) Transportation
(B) Traction
(C) Saltation
(D) Solution
Answer:
(B) Traction

Question 8.
Rock fragments move downstream by jumping continuously by the process of
(A) Siltation
(B) Saltation
(C) Solution
(D) Attrition
Answer:
(B) Saltation

Question 9.
Rock fragments remain suspended and are flown down by
(A) Solution
(B) Suspension
(C) Siltation
(D) Saltation
Answer:
(B) Suspension

Question 10.
Soluble particles are carried away by
(A) Saltation
(B) Corrosion
(C) Suspension
(D) Solution
Answer:
(B) Corrosion

Question 11.
The beginning of a river is called the
(A) Channel
(B) Silt
(C) Course
(D) Source
Answer:
(D) Source

Question 12.
The path of the river is called the
(A) Channel
(B) Bed
(C) Source
(D) Mouth
Answer:
(A) Channel

Question 13.
Small rivers joining the main river are called
(A) Tributaries
(B) Distributaries
(C) Source
(D) Mouth
Answer:
(A) Tributaries

Question 14.
Small streams that flow out of the main river are called
(A) Tributaries
(B) Source
(C) Distributaries
(D) Mouth
Answer:
(C) Distributaries

Question 15.
Two rivers meet at the –
(A) Mouth
(B) Source
(C) Confluence
(D) Channel
Answer:
(C) Confluence

Question 16.
A landform of the upper course of the river is
(A) Alluvial cone
(B) Canyon
(C) Meander
(D) Ox-bow lake
Answer:
(B) Canyon

Question 17.
Pot hole is created in the course of river.
(A) Lower
(B) Middle
(C) Upper
(D) Everywhere
Answer:
(C) Upper

Question 18.
Natural levee are formed in course of river.
(A) Upper
(B) Lower
(C) Middle
(D) Everywhere
Answer:
(C) Middle

Question 19.
Sand bars and deltas are formed in cource of river.
(A) Upper
(B) Lower
(C) Middle
(D) Everywhere
Answer:
(B) Lower

Question 20.
Materials deposited by rivers are called
(A) Moraine
(B) Debris
(C) Salts
(D) Alluvium
Answer:
(D) Alluvium

Question 21.
How much of the landform formation is influenced by the work of rivers?
(A) 30 %
(B) 50 %
(C) 60 %
(D) 70 %
Answer:
(D) 70 %

Question 22.
Who named the landform ‘delta’ for the first time?
(A) Herodotus
(B) Pithagoras
(C) Thornbury
(D) Davis
Answer:
(A) Herodotus

Question 23.
Which instrument is used to measure the water current of a river ?
(A) Barometer
(B) Altimeter
(C) Currentmeter
(D) Rain gauge
Answer:
(C) Currentmeter

Question 24.
An example of a water divide in India is
(A) Western ghats
(B) Punjab plains
(C) Eastern coastal plains
(D) Ganga plains
Answer:
(A) Western ghats

Question 25.
The delta of river – looks like the teeth of a saw.
(A) Nile
(B) Tiber
(C) Ganga
(D) Mississippi
Answer:
(B) Tiber

Question 26.
A bird’s foot delta is seen in the river
(A) Mississippi
(B) Ganga
(C) Nile
(D) Rhine
Answer:
(A) Mississippi

Question 27.
Potholes are created in the river channels due to
(A) Friction
(B) Abrasion
(C) Action of bubbles
(D) None of these
Answer:
(B) Abrasion

Question 28.
Canyons are created due to
(A) Erosion
(C) Deposition of rivers.
(B) Transportation
(D) Transportation and deposition
Answer:
(A) Erosion

Question 29.
The Majuli island is located in the river
(A) Ganga
(B) Brahmaputra
(C) Indus
(D) Narmada
Answer:
(B) Brahmaputra

Question 30.
The depressions created at the base of waterfalls are called –
(A) Potholes
(B) Plunge pools
(C) Alluvial fans
(D) Oxbow lakes
Answer:
(B) Plunge pools

Question 31.
The largest river basin of the world is
(A) Nile basin
(B) Ganga basin
(C) Amazon basin
(D) Rhine basin
Answer:
(C) Amazon basin

Question 32.
The water flowing through a river channel is measured in
(A) Knots
(B) Cm
(C) Cusec
(D) Inch
Answer:
(C) Cusec

Question 33.
The erosional work of the rivers depends on
(A) Channel gradient
(B) River load
(C) Velocity
(D) All of the above
Answer:
(D) All of the above

Question 34.
Which of the following involves removal of loosened materials of the rocks of valley walls and valley floors with the help of erosional tools?
(A) Solution
(B) Abrasion or Corrasion
(C) Attrition
(D) Traction
Answer:
(B) Abrasion or Corrasion

Question 35.
Which of the following is the mechanical tear and wear of the erosional tools in themselves?
(A) Traction
(B) Corrosion
(C) Abrasion
(D) Attrition
Answer:
(D) Attrition

Question 36.
The level at which a river completely stops erosional work is called
(A) Base level
(B) End level
(C) Maximum level
(D) Local level
Answer:
(A) Base level

Question 37.
A very deep and narrow valley is called a
(A) Gorge
(B) Canyon
(C) Pothole
(D) Plunge pool
Answer:
(B) Canyon

Question 38.
Which of the following may be defined as a vertical drop of water of enormous volume from a great height in the long profile of the river?
(A) Terraces
(B) Rapids
(C) Cataracts
(D) Waterfalls
Answer:
(B) Rapids

Question 39.
Alternate bands of hard and soft rocks give birth to a series of small step-like falls called
(A) Cataracts
(B) Rapids
(C) Cascades
(D) Terracas
Answer:
(C) Cascades

Question 40.
Which of the following refers to the bends in the longitudinal courses of the rivers?
(A) Waterfalls
(B) River terraces
(C) River meanders
(D) River valleys
Answer:
(C) River meanders

Question 41.
Which of the following is the result of both erosion and deposition?
(A) River valley
(B) River terraces
(C) Plunge pool
(D) Meanders
Answer:
(D) Meanders

Question 42.
The depositional features at the foot hills of the Himalayas are called
(A) Bhangar
(B) Bhabar
(C) Khadar
(D) None of these
Answer:
(B) Bhabar

Question 43.
Which of the deltas are formed when the river water is as dense as the sea water?
(A) Birdfoot delta
(B) Estuarine delta
(C) Arcuate delta
(D) Truncated delta
Answer:
(C) Arcuate delta

Question 44.
Ganga delta is an example of
(A) Arcuate delta
(B) Birdfoot delta
(C) Estuarine delta
(D) Truncated delta
Answer:
(A) Arcuate delta

Question 45.
Grand Canyon in United States is the work of river
(A) Colorado
(B) Mississippi
(C) Tennessee
(D) Missouri
Answer:
(A) Colorado

Question 46.
The longest river of the world is :
(A) Mississippi-Missouri
(B) Nile
(C) Ganga
(D) Amazon
Answer:
(B) Nile

Question 47.
‘Kuick point’ of a river is seen is
(A) Ox-bow
(B) Flood plain
(C) Waterfall
(D) Pot holes
Answer:
(C) Waterfall

Question 48.
Alluvial cones are formed in the rivers
(A) Upper
(B) Middle
(C) Lower course
(D) None
Answer:
(B) Middle

Question 49.
The river valley created in the dry regions due to deepcutting of soft rocks are called
(A) Gorge
(B) Canyon
(C) Hanging valley
(D) Creavasses
Answer:
(A) Gorge

Question 50.
The very deep and narrow ‘v’ shaped valley are called
(A) Gorge
(B) Canyon
(C) Interlocking Spur
(D) Waterfalls
Answer:
(B) Canyon

Question 51.
The unit for measuring the volume of water flowing through a certain part of a river is said to be 1 cusec, when the volume of water flowing through is
(A) 1 cubic meter
(B) 1 cubic feet
(C) 1 cubic inch
(D) 1 cubic centimeter
Answer:
(D) 1 cubic centimeter

Question 52.
When the speed of the river increase by two times, its carrying capacity increased by
(A) 7
(B) 2
(C) 3
(D) 64 times
Answer:
(D) 64 times

Question 53.
The main cause of submergence of the island of sundarbans is
(A) Heavy rainfall
(B) Cyclone
(C) Rise in sea level
(D) Flood
Answer:
(C) Rise in sea level

Question 54.
The sediments depositions on the convex side of meanders are called
(A) Pool
(B) Point bar
(C) Pluge pool
(D) flood plain.
Answer:
(B) Point bar

Question 55.
A falline is a
(A) Band of hard rocks
(B) Chain of waterfalls
(C) Steepness of valley side
(D) All of these
Answer:
(B) Chain of waterfalls

Fill in the blanks : 1 Mark

1. V-shaped river valleys are found in the ________ stage of the river.
2. The formation of rapids and waterfalls is found in the _______ course of the river.
3. The delta in Inda is the largest delta of the world.
4. The breaks in the channel gradient caused by rejuismation of rivers are called ________.
5. The average height of natural levees is ________.
6. If the speed of the river is doubled, its carrying capacity increases by _______ times.
7. The gersoppa waterfalls are also known as ________.
8. The _______ delta of India is an active delta.
9. River _______ is known as the sorrow of Bengal.
10. The waterfalls move _______ of the river.
11. The narrow plain region between two rivers is called the ________.
12. The landform which separates two river systems is called the ________.
13. _______ lakes are created near delta regions.
14. Deltas are created in the _______ course of rivers.
15. Alluvial fans are created at the _______ of mountains.
16. River _______ is an inland river of India.
17. The New Moore island is known as _______ in Bangladesh.
18. A fault lying across the river in a mountanious region gives rise to ________.
19. In the upper course of a river, downcutting of valleys mainly occure due to ________.
20. The longest river of the world is river _______.
21. The island of Newmoore and Ghoramara have submerged due to ________.
22. The river erodes least in the _______ course.
23. The term meander came from the river ________.
24. Holes formed by abrason on river bed are called _______.
25. According to the name of _______ river, the zigzag course of a river is as meander.
Amswer:
1. Youthful
2. Upper/Youthful
3. Ganga-Brahmaputra
4. Knick points
5. 10 m
6. 64
7. Jog falls
8. Sundarban
9. Damodar
10. Headward
11. Doab
12. Water divide
13. Oxbow
14. Lower
15. Foothill
16. Luni
17. South Talpatti
18. Waterfalls
19. Abreasion
20. Nile
21. Rise in the sea level
22. Lower
23. Buyuk meanders
24. Pot holes
25. Meanders.

State True or False : 1 Mark

1. Interlocking spurs are found in the lower course of the rivers. [ ]
2. If slope of land increases, the speed of river reduces. [ ]
3. No delta has developed at the mouth of river Narmada. [ ]
4. River Godavari is an ideal river. [ ]
5. River Brahmaputra is the longest river of India. [ ]
6. The river Ganga rises from the Chemuyung Dung glacier. [ ]
7. The New Moore is a newly formed island of the Sundarbans. [ ]
8. The process of friction of rock fragments with the river bed is called abrasion. [ ]
9. The middle course of the river Ganga lies between Allahabad and Patna. [ ]
10. Canyans are formed in cold climatic regions. [ ]
11. The rivers mostly erode sidewards in the upper course. [ ]
12. Meanders are created when the speed of the river increases. [ ]
13. River Ganga is a perenial river. [ ]
14. The mouths of the rivers are generally wide. [ ]
15. Deep creeks and estuaries are found in the Sundarban regions. [ ]
16. The plains formed at the base level of erosion by rivers has been termed peneplains by Davis. [ ]
17. The Dasam falls have been formed in the river Subarnarekha [ ]
18. ‘Meander’ comes from the river Menderes in Turkey. [ ]
19. The largest river island of the world is Ilha-da-Marajo. [ ]
20. The hairpin bend of a river is also called the ‘elbow of river capture’. [ ]
21. The main work of the river in its mountaneous course is erosion. [ ]
22. Work of river starts above the snowline. [ ]
23. Potholes are created in the riverbeds due to abrasion and attrition. [ ]
24. The sea level is the last limit of erosion. [ ]
25. The Grand Canyon lies in the course of river Colorado. [ ]
26. The scientific study of the river is known as potamology. [ ]
27. Rapids are larger than cascade in dimension. [ ]
28. Waterfalls are mostly formed at the upper stages of the rivers. [ ]
29. Oxbow lakes are seen in the upper course of a river. [ ]
30. Canyons are ‘U’ shaped valley. [ ]
31. Pot holes are formed at the base of waterfall. [ ]
32. The confluence of Alakananda and Bhagirathi rivers is at Devprayag. [ ]
Answer:
1. False
2. False
3. True
4. False
5. False
6. False
7. True
8. True
9. True
10. False
11. False
12. False
13. True
14. True
15 . True
16 . True
17. True
18. True
19. False
20. True
21. True
22. True
23. True
24. True
25. True
26. True
27. False
28. True
29. False
30. False
31. False
32. True

Match the following :

List 1	List 2
A. Arcuate delta	1. Mississippi delta
B. Birdfoot delta	2. Yellow river delta
C. Esturanine delta	3. Nile delta
D. Abandoned delta	4. Hudson delta

codes:

Answer:
[D]

Answer in few words : 1 Mark

Question 1.
What is a river?
Answer:
A large stream of flowing water along the slope on the earth’s surface.

Question 2.
What are the main works of a river?
Answer:
Erosion, Transportation, Deposition.

Question 3.
How many courses does an ideal river have ?
Answer:
Three courses – upper, middle, lower.

Question 4.
Where does a river start and end ?
Answer:
The river starts at the source and ends at the mouth.

Question 5.
What is a river basin ?
Answer:
The area drained by the main river, tributaries and distributaries.

Question 6.
Name some landforms of the upper course of the river.
Answer:
V-shaped and I-shaped valleys, gorges, canyons, pot holes, waterfalls etc.

Question 7.
Name some landforms of the middle course of the river.
Answer:
Alluvial cones and fans, flood plains, natural levee, meanders, ox-bow lakes etc.

Question 8.
Name some landforms of the lower course of the river.
Answer:
Sand bar, delta, braided channel etc.

Question 9.
Which is the largest delta of the world ?
Answer:
The Ganga-Brahmaputra delta.

Question 10.
Where was the Lohachara island situated ?
Answer:
Sundarban.

Question 11.
How far does the upper course of river Ganga lie?
Answer:
Gomukh to Haridwar.

Question 12.
On which course of the river depositional activities are the least?
Answer:
Upper course.

Question 13.
What is the curved of a river is called ?
Answer:
Meandar.

Question 14.
Name the place where the river meets the sea.
Answer:
Estuary.

Question 15.
What is the sediment carried by the river called ?
Answer:
Bed load.

Question 16.
Name the process of erosion in which air bubbles trapped in small spaces implode to erode rocks.
Answer:
Cavitation.

Question 17.
Which is the longest estuary of the world ?
Answer:
Gulf of Ob.

Practicing with West Bengal Board Class 10 History Book Solutions and WBBSE Class 10 History Sample Question Paper Set 3 alongside detailed explanations can lead to a deeper understanding of the subject.

West Bengal Board Class 10 History Model Question Paper Set 3

Group A

1. Choose the correct answers to the following: 1×20=20

Question 1.
Of the following who translated a text book on anatomy into Sanskrit ?
a. Madhusudan Gupta
b. Jagadish Chandra Bose
c. Dasarathi Roy
d. Sridhar Kathak
Answer:
a. Madhusudan Gupta

Question 2.
Of the following which often tells story from life?
a. History
b. An autobiography
c. A memoir
d. A short story
Answer:
c. A memoir

Question 3.
In which of the following years was Hindoo Patriot published ?
a. 1800
b. 1813
c. 1853
d. 1857
Answer:
c. 1853

Question 4.
Of the following the name that does not in any way go with the spread of Western education?
a. Raja Radhakanta Deb
b. Raja Rammohan Roy
c. Ramendrasundar Trivedi
d. Kaliprasanna Singha
Answer:
d. Kaliprasanna Singha

Question 5.
Of the following who left the Brahmo Samaj after a breach with Debendranath Tagore ?
a. Shivnath Shastri
b. Rammohan Roy
c. Keshab Chandra Sen
d. Dwarakanath Tagore
Answer:
c. Keshab Chandra Sen

Question 6.
Of the following who launched a very strong movement against the practice of sati?
a. Sivnath Shastri
b. Rammohan Roy
c. Keshab Chandra Sen
d. Radhakanta Deb
Answer:
b. Rammohan Roy

Question 7.
Of the following who made liberal contribution for the spread of education in Bengal ?
a. Keshab Chandra Sen
b. Raja Rammohan Roy
c. Dwarakanath Tagore
d. Haji Muhammad Mohsin
Answer:
d. Haji Muhammad Mohsin

Question 8.
Of the following who mooted the idea of setting up the Ramakrishna Mission?
a. Sri Ramakrishna Deva
b. Bijay Krishna Goswamee
c. Swami Vivekananda
d. Debendranath Tagore
Answer:
c. Swami Vivekananda

Question 9.
In which of the following places did the Chuar Rebellion take place ?
a. Hooghly
b. Rangpur in present Bangladesh
c. Chotonagpur
d. Bankura and Medinipur
Answer:
d. Bankura and Medinipur

Question 10.
One of the leaders of the Kol rebellion was :
a. Kanu
b. Buddhu Bhagat
c. Birsa Munda
d. Majnu Shah
Answer:
d. Majnu Shah

Question 11.
Of the following who founded the religious sect Pagal-Panthis ?
a. Dudu Mian
b. Karam Shah
c. Joa Bhagat
d. Durjan Singh
Answer:
b. Karam Shah

Question 12.
Of the following who came to be known as the Governor-General and Viceroy of India following the Queen’s Proclamation ?
a. Lord Dalhousie
b. Lord Canning
c. William Bentinck
d. Warren Hastings
Answer:
b. Lord Canning

Question 13.
Of the following who was the founder of the Wahabi Movement ?
a. Titumir
b. Mir Nisar Ali
c. Muhammad Abdul Wahab of Nejd
d. Haji Shariatullah
Answer:
c. Muhammad Abdul Wahab of Nejd

Question 14.
Of the following find the incompatible one :
a. Jibansmriti
b. Jibaner Jharapata
c. Sattur Batsar
d. Gora
Answer:
d. Gora

Question 15.
Of the following who was the editor of the Grambarta Prakashika?
a. Kangal Harinath Majumdar
b. Kaliprasanna Singha
c. Dinabandhu Mitra
d. Girish Chandra Ghosh
Answer:
a. Kangal Harinath Majumdar

Question 16.
In which of the following years was the first Hindu widow remarriage took place?
a. 1855
b. 1856
c. 1857
d. 1858
Answer:
b. 1856

Question 17.
The woman revolutionary who made a daring attack upon the Europeans:at the Assam-Bengal Railway European Club was :
a. Bina Das
b. Kalpana Dutta
c. Pritilata Waddedar
d. Ashalata Sen
Answer:
c. Pritilata Waddedar

Question 18.
Of the following who was the first to use the term dalit meaning oppressed people?
a. Jotiba Phule
b. Harichand Thakur
c. Mahatma Gandhi
d. B. R. Ambedkar
Answer:
a. Jotiba Phule

Question 19.
Of the following who is regarded as the ‘father of the Namasudra renaissance?
a. Harichand Thakur
b. B.R. Ambedkar
c. Mahatma Gandhi
d. Guruchand Thakur
Answer:
d. Guruchand Thakur

Question 20.
Under whose leadership Hyderabad was annexed to the Indian Union by ‘police action’?
a. General Cariappa
b. General J.N. Chaudhuri
c. General Subrata Chaudhuri
d. None of the above
Answer:
b. General J.N. Chaudhuri

Group B

2. Answer the following Questions

Attempt one question from each sub-group: In all 16 questions 1×16=16

Answer each of the following questions in one sentence :

Question 1.
Name the memory picture written by Rabindranath Tagore.
Answer:
Jibansmriti is the name of the memory picture written by Rabindranath.

Question 2.
Who was author of the book entitled Letters from a Father to His Daughter?
Answer:
‘Father to His Daughter’ is the book authored by Jawaharlal Nehru.

Question 3.
When was Calcutta Medical College of Bengal established ?
Answer:
It was in 1835 that the Calcutta Medical College of Bengal was established.

Question 4.
Who was the first lady to become the President of the Congress ?
Answer:
Annie Besant was the first lady to become the President of the Indian National Congress.

Identify which of the following is ‘True’ or ‘False’ :

1. While speeches are considered primary source the autobiography and memoirs are the secondary source of history.
Answer: True

2. Titumir of the Barasat Revolt was also known as Mir Nisar Ali.
Answer: True

3. The Munda rebellion is classified as a working class movement.
Answer: False

4. Bina Das was in favour of Non-violent movement.
Answer: False

Match column ‘A’ with column ‘B’

A	B
1. First printing press and newspaper	(a) Vernacular Press Act
2. First Bengali news weekly	(b) Lord Ripon
3. Revocation of the Vernacular Press Act	(c) Bangal Gazette
4. Lord Lytton	(d) Hicky

Answer:
1-d, 2-c, 3-b, 4-a

4. Identify the following places in the given map of India :

1. The area where Ramakrishna Mission is located.
2. The area where Wahabi Movement began.
3. The region in Bangladesh where peasantry revolted in 1870 .
4. The area where Mangal Pandey raised the banner of rebellion.
Answer:
See the Map attached
Or
(Only for blind students)

1. was one of the leaders of the Fakirs in the Sannyasi-Fakir rebellion.
Answer: Majnu Shah

2. The play Neel Darpan was composed by
Answer: Dinabandhu Mitra

3. was known as the ‘Grandfather of Indian nationalism’.
Answer: Rajnarayan Bose

4. Hyderabad was annexed to the Indian Union in
Answer: 1949

Select the correct interpretation of the following statements :

1. Statement : In Bamabodhini, a Bengali periodical, strong emphasis was was given on women issues.

Interpretation 1: The paper focused on the needs of the womenfolk
Interpretation 2: Bamabodhini continued to be published till 1923
Interpretation 3: Bamabodhini helped to bring about women’s progress in education and social matters.
Answer:
Interpretation 2: Bamabodhini continued to be published till 1923

2. Statement: Derozio promoted advanced ideas through his lectures.

Interpretation 1: Derozio moulded the minds of his students.
Interpretation 2: He constantly encouraged his students to think freely and questioning all authority.
Interpretation 3: Under Derozio’s influence his students drew inspiration from Bacon, Hume, etc.
Answer:
Interpretation 2: He constantly encouraged his students to think freely and questioning all authority.

3. Statement: The play Neil Darpan was written in the background of the. Indigo Revolt of 1859.

Interpretation 1: It exposed the inhuman villainy of the indigo planters.
Interpretation 2: The torture perpetrated by the indigo planters were mostly Europeans.
Interpretation 3: In reality the play highlighted the oppressive machinery of the colonial rulers.
Answer:
Interpretation 1: It exposed the inhuman villainy of the indigo planters.

4. Statement: The British Government of India instituted the Meerut Conspiracy Case (1929)

Interpretation 1: To suppress labour movement which was the result, it was thought, due to socialist influence.
Interpretation 2: In the case most of the Communist and trade union leaders were arrested.
Interpretation 3: The then-British Government became alarmed at the growing unrest among the workers.
Answer:
Interpretation 1: To suppress labour movement which was the result, it was thought, due to socialist influence.

Group C.

3. Answer the following questions in 2 or 3 sentences (any 11)

Question 1.
Can autobiography be considered as a source of history?
Answer:
Indeed, autobiography is a primary source for the reconstruction of history. For, autobiography directly tells the story of life of the person.

Question 2.
Name the first two graduates of the University of Calcutta.
Answer:
The first two graduates of the University of Calcutta were Bankim Chandra Chatterjee and Joddunath Bose.

Question 3.
To which educational institution did Mohammad Mohsin contribute liberally ?
Answer:
Haji Mohammad Mohsin was a wealthy man. In his charitable efforts he made no distinction between man and man. He made remarkable gift to the Hooghly College (presently Hooghly Mohsin College).

Question 4.
Who founded the Nababidhan ?
Answer:
The initial breach between Keshab Chandra Sen and Debendranath Tagore led to the formation of Brahmo Samaj of India. Yet formation of another religious faith became inevitable in 1881 when Keshab Chandra Sen founded Nababidhan.

Question 5.
Who were the adivasi or tribals ?
Answer:
The adivasi or tribal communities of India as distinguished from the peasantry were also basically peasants. They earned their livelihood through shifting cultivation and collection of fruits and roots from forest.

Question 6.
What social reforms did the Brahmo Samaj aim at?
Answer:
The Brahmo Samaj aimed at promotion among different religious groups a faith in the unity of the divine and of man. Another objective of the Brahmo Samaj was the welfare of the common people.

Question 7.
What do you understand by the term ‘revolution’?
Answer:
‘Revolution is one that brings about fundamental change in the politicosocio-economic level of a country. The French Revolution or Russian Revolution may be cited as examples of revolution.

Question 8.
What was the characteristic feature of the Kol Rebellion?
Answer:
The characteristic feature of the Kol rebellion was that the Kol tribesmen were not alone to give a fight to the British. The Kols got direct support from other tribesmen like Hos, Oraons and Mundas. Thus it goes to the credit of the Kols that could garner support of the fellow tribesmen in a fight against the British.

Question 9.
Why was the ‘age of association’ crucial to the country?
Answer:
In the absence of any political party it is not at all possible to express the grievances of people to the political authority. In India, such deficiency was made up when a number of political associations came into existence in the mid-nineteenth century. Thus began the ‘age of association’ when people could raise their legitimate demands and place them before the colonial government.

Question 10.
What is stated in the Bartaman Bharat of Swami Vivekananda?
Answer:
In Bartaman Bharat Swami Vivekananda predicted formation of an ideal state in India. According to him, the ideal state would be one in which the knowledge of the priest period, the culture of the military as also the ideal of equality are brought into harmony.

Question 11.
How did printing press help the spread of education ?
Answer:
Printing press, indeed, helped the spread of education in India. Printing of books within a short time facilitated availability of reading materials. Thus printed books became a medium for the dissemination of knowledge.

Question 12.
Why did Rabindranath found Sriniketan?
Answer:
Rabindranath set up Sriniketan at the contiguous campus of Visva Bharati. The objective was to help the villagers to solve their own problems. Also an emphasis was laid on a scientific study of the village problem.

Question 13.
Who was Baba Ramchandra?
Answer:
In 1919 Baba Ram Chandra was the first to lead a peasant protest against the landlords. In 1920 he set up Oudh (Awadh) Kisan Sabha. He was a sannyasi (mendicant) who earlier had been to Fiji as a bonded labour

Question 14.
Why is Bina Das remembered ?
Answer:
In 1929 Bina Das joined Bhupal Bose’s revolutionary group. She engaged herself in carrying on revolutionary activities. In 1932 Bina Das made an attempt o the life of Stanley Jackson, the then Governor of Bengal.

Question 15.
Why is Potti Sreeramulu remembered ?
Answer:
Potti Sreeramulu was a devout follower of Mahatma Gandhi. He worked throughout his life for humanitarian causes. He became famous for undertaking a fast for the formation of Andhra for the Telegu-speaking people of Madras.

Group D

4. Answer the following questions in 7/8 sentences: 

(Attempt one question from each sub-group: in all 6 questions)

Question 1.
How did Rammohan Roy help the spread of Western education?
Answer:
Raja Rammohan Roy was the first Indian to feel the need for Western education, and as such came to be known as the ‘First Modern Man of India’. In a letter addressed to Lord Amherst Rammohan categorically pointed out that no useful purpose will be served establishing college for Sanskrit learning. Noticing apathy of the government in establishing institutions where Western scientific education would be taught Rammohan himself founded Anglo-Hindu School in 1822.

In 1825 Rammohan founded the Vedanta College where along with Western science and philosophy the students were to be taught Vedanta philosophy. Another significant contribution of Rammohan in the field of Western education was that he drew the Christian Missions to this field. He requested the Church of Scotland Assembly to send out competent teachers to spread English education in India.

Question 2.
How did Iswarchandra Vidyasagar campaign for widow remarriage ?
Answer:
It was Iswarchandra Vidyasagar who began a campaign for widow remarriage during the mid-nineteenth century. He waged a long struggle in favour of widow remarriage. However, he realized that the campaign for widow remarriage would have an appeal to the general people if it was backed by reference to Shastric instructions.

Thus Iswarchandra began studying sacred books. Vidyasagar raised his powerful voice, backed by the weight of immense traditional learning in favour of widow remarriage. At last he found what he wanted in a verse of the Parasara Samhita.

In one of the Slokas it has been categorically stated that a second marriage is sanctioned for women under certain conditions, and one of the conditions referred to is the death of husband of a married woman. It was in this manner Vidyasagar sanctified the remarriage of Hindu widows.

Question 3.
What was the importance of the Queen’s Proclamation?
Answer:
Queen Victoria by a Proclamation announced on 1 November 1858 assumed the responsibility of the Indian administration in her own hands. The importance of the Proclamation were :

• The honorific title of Viceroy was added to the ‘Governor-General of India’.
• Lord Canning so far known as the Governor-General of India also became the first Viceroy of India.
• In her Proclamation Queen Victoria also announced some changes in the governmental policy to be pursued by the British in India. She made it clear that the British Government had no desire of further territorial expansion in India.
• The Queen also stated that the British would in no way interfere with the established customs or religions of the Indian people.
• As per the Proclamation there was an extensive reorganization of the army and civil administration.

Question 4.
How did Anandamath help the spread of nationalism ?
Answer:
Study of the literary works of great litterateurs of nineteenth century Bengal reveals nationalist feelings embedded in them. In this context Anandamath of Bankim Chandra Chatterjee may be discussed. Anandamath of Bankim Chandra bears historic worth in the narrative of nationalism in modern India.

Written in the background of the memory of Sannyasi Rebellion, the novel centres around the organization of the santans (or children of Mother India). Now that the Mother is in chains of the foreigners her children vow to tear asunder the bondage.

• The novel narrates how the children of the Mother take up arms against the rule and domination of the aliens. It is in Anandamath that the Indian people get the famous song, Bande Mataram.
• The opening stanza of the song is full of appreciation for the natural possessions that adorn the Mother.
• In the song the sacredness of the land has been raised to a religious level. The song combines patriotism with religious fervour.
• Anandamath was a Bible for the secret revolutionaries. In fact, they modeled their societies on the organization founded by Satyananda, the hero of the novel. Thus Anandamath helped the spread of Indian nationalism.

Question 5.
What were the contributions of Hindu Mela to the cause of Indian nationalism?
Answer:
The Hindu Mela had immense contributions to the cause of Indian nationalism.

• The Hindu Mela used to hold annual sessions. On such occasions fairs were organized attended by thousands of people. Display of various products of Indian arts and crafts encouraged the native producers.
• The Hindu Mela also worked for the development of national literature, national song, national gymnastics, etc.
• The Mela also drew into the national movement personalities like Sivnath Shastri, Bipin Chandra Pal, Sisirkumar Ghose and many others.
• The Hindu Mela by fostering the spirit of self-help paved the way for foundation of the national movement.
•  Emphasis on the indigenous products in the fairs (mela) organized was a farsighted move and the industrial exhibitions were the forerunners of the Industrial Exhibition organized by the Indian National Congress in 1896.

Question 6.
What was Rabindranath’s idea of education ?
Answer:
Elaborating his own ideas about the aims of education Rabindranath said that the fundamental purpose of education was not “….merely to enrich ourselves through the fullness of knowledge…”. Rather he believed that the purpose also was to establish bond of love and friendship between man and man. Thus it may be said that Rabindranath’s approach to education was humanistic.

He believed in an inner harmony amongst man, nature and god. In Rabindranath’s idea of education teachers had to be imaginative. The teachers should understand the child, and help the child to develop curiosity in them. Tagore further felt that the creative learning could be encouraged only within natural environment. Living in harmony with nature, children would be able to cultivate their natural creativity.

Question 7.
What was the nature of women’s participation in the revolutionary Struggle
Answer:
In the revolutionary struggle participation of women presented a different picture than that of non-violent struggle.

i. Women’s involvement in the non-violent struggle had the support and encouragement of Gandhiji. But the women who participated in the armed struggle joined it on their own. That is to say, there had been no encouragement from any quarter to enthuse the women to join the revolutionary struggle.

ii. In fact, the revolutionary secret societies made no concerted efforts to encourage the participation of women as Mahatma Gandhi had done in regard to the non-violent activities.

iii. Another important point to be noted is that direct participation of women in the revolutionary movement was not feasible also due to certain constraints. First, women were not allowed by their male relatives to join the revolutionary secret societies. Second, the risk was too high to allow women to participate in revolutionary feats on an equal basis with men.

iv. However, in general the indirect participation of women helped the revolutionaries silently from the background. In the above context the revolutionary activities of Pritilata Waddedar and Kalpana Datta may be discussed.

Question 8.
What was the main point of the debate between Gandhiji and Ambedkar regarding the rights of the dalits ?
Answer:
There is little doubt that both Gandhi and Ambedkar were very much aware of the problem of untouchability or the dalits. Yet there was sharp difference between the two regarding the dalit issue.

i. That there was little in common in the perception between the two came to the forefront in the early 30s of the nineteenth century.

ii. Gandhiji refused to view the dalits as a minority who should be given political safeguards. Rather he considered it essentially a social problem, and that was to be tackled by the Hindu community itself. Contrarily, Ambedkar describing the dalits as ‘slaves’ advocated for communal representation of the dalits on the ground that ‘untouchability constitutes a definite set of interests which the untouchables alone can speak for.’

iii. Throughout 1920s Ambedkar had a soft spot for Gandhi as he took him as one different from the elitist Brahmanic leaders he (Ambedkar) hated. The real break between the two surfaced during the events of the Round Table Conference of 1932.

Group E.

5. Answer any one question in 15/16 sentences :

Question 1.
Write about the nature of the Revolt of 1857
Answer:
The nature of the Revolt of 1857 is a very contentious issue, and debate over it started from the very moment of its happening.

1. Opinions are sharply divided as to whether the Revolt of 1857 was mere a mutiny or a War of Independence.

2. Considered from the nature of the rising the old school of historians found it difficult to call it a War of Independence on the following grounds

• There was no definite political ideal before the rebels. Though expulsion of the British was the immediate goal, there was no co-ordinated plan to establish an independent government in place of the British.
• There was no plan, no co-ordination among the rebels in different parts of the country. The fact that at least some of the zamindars and talukdars (landed magnates) participated in the rebellion would at best give it a feudal character as Jawaharlal Nehru pointed out. c Common people did not participate in any measure that can legitimately give it the name of a ‘national rising’.

3. Professor S. N. Sen in his book entitled Eighteen Fifty-seven concluded that the mutiny of 1857 was not simply a rising of the sepoys. He argued that a national rising does not require participation of all people. Only an influential section of people had participated in the revolutions of France and America. On such arguments Professor Sen calls it a ‘national rising’, although to a limited extent.

4. Professor Rames Chandra Mazumder’s arguments are also somewhat identical with those of Professor Sen. According to him, what began as a mutiny ended in certain areas in an outbreak of the civil population.

5. There is, however, no dearth of other opinions. As pointed out by Professor Sekhar Bandyopadhyay, V. D. Savarkar by describing the revolt of 1857 as the ‘Indian War of Independence’ directly drafted it into the historiography of Indian nationalism.

Question 2.
What was the participation of the peasants in the Anti-Partition Movement? What was the Bardoli satyagraha?
Answer:
A. Participation of the Peasants: The anti-partition movement assumed an all-India character in which different classes of people participated. Despite the popular character of the anti-partition movement it must be admitted that it was largely confined to the urban middle class. The peasants’ participation was very much limited.

Indeed, the Congress leadership did call upon the peasants to start a no-rent campaign. However, in some way the participation of peasants in the movement was significant. The indigo peasants of Champaran in Bihar rose in rebellion. Peasants’ disturbances took place in Assam and Mymensingh (in present Bangladesh).

The Muslim peasants of Barisal (in present Bangladesh) were led by Aswini Kumar Datta. The Left politics did not emerge in India during the anti-Partition movement. As such there was no question of the Leftists’ leadership amongst the peasants.

B. Bardoli Satyagraha: The first civil disobedience movement was staged by the peasants of Bardoli in the Surat district of Gujarat. In 1926 when the time of revision of land revenue was due at Bardoli it was found that the hike was unprecedented. The burden on the peasants was 22% to 60 % more than the previous rate of tax.

The peasants of Bardoli thereupon began satyagraha under the leadership of Vallabhbhai Patel who had the blessings of Gandhiji. The Bardoli Satyagraha was formally launched on 12 February 1928. The satyagraha constituted an important chapter in the freedom movement of India. a. Bardoli Satyagraha became the symbol of peasants’ protests in the country.

Question 3.
Write in short about the participation of the working class in the Quit India Movement.
Answer:
The Quit India Movement did not leave the working class untouched. The formation of Congress ministries in different provinces following election in 1937 gave a boost to the working class movement.

i. In fact, during the tenure of the Congress ministries between 1937 and 1939 there was a phenomenal rise in the trade union movement. During this period the number of trade unions increased from 271 to 562.

ii. It must be pointed out here that the pro-labour attitude of the Congress governments in the provincial level also served as an encouragement to the trade union activities.

iii. Even the Congress Working Committee in a resolution denounced the repressive measures taken on the workers by the non-Congress provincial ministries of Bengal and Punjab.

iv. Another significant feature was that during the period under reference strikes organized by the trade unions mostly ended successfully, with victory of the struggling workers.

v. The Quit India Movement formally began on 9 August with arrests of most of the prominent national leaders including Gandhiji. As the news of the arrests spread workers of various places of the country went on strikes and hartals that lasted for a week.

Delhi, Lucknow, Jamshedpur, Madras, Bangalore, etc. were some of the main centres of the strikes. In some places the strikes continued for longer periods. The Tata Steel Plant was shut down for thirteen days. In Ahmedabad the textile workers continued the strike for three and half months.

vi. Following the ‘People’s War’ line the communists dissociated themselves from the Quit India Movement. They lent no support to the industrial strikes by the working class. Rather the communists followed a policy of industrial peace so that the workers could concentrate on production.

Group F

6. Answer the questions in a complete sentence

Question 1.
What is the name of the autobiography of Bipin Chandra Pal ?
Answer:
Sattar Batsar (Seventy Years) is the name of the autobiography of Bipin Chandra Pal.

Question 2.
Who was the editor of Bangadarshan ?
Answer:
The journal Bangadarshan was published by Bankim Chandra Chattopadhyay.

Question 3.
Who was the author of Hootum Pyanchar Naksha?
Answer:
Hootum Pyanchar Naksha was authored by Kaliprasanna Singha.

Question 4.
Mention the name of a woman leader of the Swadeshi Movement.
Answer:
Ashalata Sen was a woman leader during the Swadeshi Movement.

Question 5.
Who organized the Anti-Circular Society ?
Answer:
Krishnakumar Mitra organized the Anti-Circular Society.

7. Answer the following questions in 2/3 sentences :

Question 1.
What do understand by the term ‘Urban History’?
Answer:
Urban History literally means history of cities. Till very recently the subject was much neglected, but of late the urban history has received the attention of modern historians.

Question 2.
Can periodicals and newspapers be regarded as a source of history ?
Answer:
Indeed, newspapers and periodicals are regarded as an important source for the reconstruction of history. While newspapers are the primary source of history, the periodicals are the secondary source.

Question 3.
What came to be known as the Corridor Warfare?
Answer:
Benoy Bose, Badal Gupta and Dinesh Gupta, the revolutionary trio named ‘Benoy-Badal-Dinesh’ of the Bengal Volunteers group were involved in an encounter with police inside the Writers’ Buildings that came to be known as the Corridor Warfare. The encounter followed after the revolutionaries fatally shot Simpson, the then Inspector-General of Police.

Question 4.
What was the ‘carrot and stick’ policy followed in the accession of the princely (or native) states of India.
Answer:
It was Vallabhbhai Patel who with great skill and diplomacy successfully completed the accession of the Princely States with the Indian Union. He had followed the dual policy of ‘carrot and stick’ meaning while invitation was made to the princes to join the Indian Union peacefully the recalcitrant elements would be forced to accede to.

Detailed explanations in West Bengal Board Class 10 Geography Book Solutions Chapter 1.1 Exogenetic Forces offer valuable context and analysis.

WBBSE Class 10 Geography Chapter 1.1 Question Answer – Exogenetic Forces

Answer in short : 2 Marks

Question 1.
What do you mean by landform ?
Answer:
Landform refers to the shape, height, ruggedness, slope etc. of the earth’s surface. In a nutshell, landform is the appearance of the surface of the earth. According to W.M. Davis, ‘Landscape’ is the function of structure, process and stage.

Question 2.
What do you mean by landform creating processes ?
Answer:
The physical and chemical processes that have been working since the birth of the earth to create, change, reform or rebuild a landform are called landform creating processes. In short, the processes that act inside and outside the earth’s surface and lead to formation of various landforms are called landform creating processes.

Question 3.
What are exogenetic processes of landform building ?
Answer:
The processes of landform creation that derive their force from natural sources like sun, wind, heat, air pressure, humidity, rainfall, river, glacier, sea waves etc. are called exogenetic processes. The main sources of energy of such processes are the sun and the earth’s atmosphere.

Question 4.
What do you mean by base level of erosion ?
Answer:
A base level of erosion is an imaginary surface of irregular shape, inclined towards the lower end of the principal river or its trunk, under which the stream and its tributories were unable to erode. It can be further divided into ground base level, temporary base level and local base level.

Question 5.
In how many parts can exogenetic forces be divieded ?
Answer:
Exogenetic forces on landform creation can be divided into two parts – i. Static physical forces : atmospheric heat, pressure, humidity, cloud cover, rainfall, dew frost etc. ii. Dynamic physical forces : river, wind, glacier, mass wasting, sea waves, ocean currents etc.

Question 6.
What is gradation?
Answer:
According to Chamberlen and Salisbury (1904) gradation is a process by which the uneven and rough surface of the earth is gradually smoothened by erosion or deposition in order to attain a plain and polished landform. This is brought about by the exogenetic processes by changing the heights of the different landforms.

Question 7.
Classify the exogenetic processes.
Answer:

Question 8.
What is degradation?
Answer:
The process by which the height of mountains, hills and plateaus are reduced by erosion and mass removal, which result in lower landforms is known as degradation as a whole. The processes of degradation can be divided into weathering, erosion and mass wasting.

Question 9.
What is weathering ?
Answer:
Weathering comes from the word ‘weather’. Weathering refers to breaking or fragmentation of rocks by the action of different weather elements like heat, pressure, humidity, cloudiness, rainfall, dew etc. The broken rock fragments lie in situ.

Question 10.
What is erosion?
Answer:
The process of removal of broken and fragmented rock material by dynamic forces of nature like river, wind, glacier, waves etc. thus reducing the height of the original landform is called erosion.

Question 11.
What is mass wasting ?
Answer:
In hilly regions, if rain water percolates through the soil or rocky beds, the materials get loosened. These soil and rocky materials may fall down in huge masses along the slope due to gravitational force. Such movement of earth materials in huge masses along slope of land is called mass wasting.

Question 12.
What is aggradation?
Answer:
The earth materials brought down by the dynamic forces of nature (river, glacier, wind etc.) due to degradation are deposited in the lower slopes in lowlands, basins or depressions. The process of such accumulation of materials, thus increasing the height of the current landform, is known as aggradation.

Question 13.
Name some landforms formed by degradation.
Answer:
Landforms created by degradation are : monadnock, inselberg, mesa, butte, dhand of desert region, corrie, corrie lake etc.

Question 14.
Name some landforms formed by aggradation.
Answer:
Landforms created by aggradation are : loess plains, flood plains, alluvial cones and fans, moraines, drumlin, outwash plains, sand bars, beaches, stalactite, stalagmite etc.

Question 15.
What is the last limit of erosion?
Answer:
When the exogenetic processes cut and lower an undulating rugged highland to a smooth slope where no more erosion occurs, this is known as the last limit of erosion.

Question 16.
What are the biological processes of landform creation?
Answer:
The exogenetic processes that cause weathering, transportation, erosion and deposition of earth materials due to interference of biological agents like man, plants and animals are called biological processes of landform creation.

Question 17.
What is denudation?
Answer:
When the weathered earth materials are removed from their position by erosion and mass wasting, the surface beneath the debris becomes open and forms a new landform. This process of opening up of the new surface of the landform is called denudation.
Denudation = Weathering + erosion + mass wasting.

Question 18.
How can mass wasting be classified?
Answer:
Mass wasting can be classified into two parts – i. Slow flowing and ii. Fast flowing.

Question 19.
What do you mean by gradational forces?
Answer:
Landforms are initially formed with the help of geotectonic forces that work from within the earth’s interior. These are further sculptured by the static and dynamic forces that act on the surface of the earth. These forces tend to reduce the landforms to a smooth rolling plain or graded profile. These forces are known as gradational force.

Question 20.
Name the different gradational forces.
Answer:
The gradational forces are broadly classified into two parts –
i. Static forces – These are the forces that have no motion, but help in formation or sculpturing of landforms. Eg. – Heat, pressure, humidity, cloudiness, rainfall etc.
ii. Dynamic forces – These are the forces that have motion and help actively in changing landforms. Eg. – rivers, wind, waves, glaciers, ocean currents etc.

Question 21.
How can the degradation processes be classified?
Answer:
Degradation processes can be classified into – i. weathering ii. erosion iii. mass wasting.

Question 22.
What is the outcome of gradation?
Answer:
By gradation, the lower regions are filled up and elevated while the higher regions are reduced, so that ultimately a smooth and rolling plain is formed, where neither erosion nor deposition is required.

Question 23.
Why do some geologists refuse to consider weathering as a part of gradational process?
Answer:
In weathering, rock fragments break off from parent rocks, but they are not removed from position. They lie in dumps where they have been broken from. Thus, height or altitude of the landform is not much reduced, and no gradation is achieved unless the materials are removed. Hence, some geologists refuse to consider weathering as a part of gradational process.

Question 24.
What are biological processes of gradation?
Answer:
The processes by which plants, animals and man interfere and cause weathering, transport and erosion of rock fragments, deposition of these debris in low lands, thus causing formation of a graded profile are called biological processes of gradation.

Question 25.
Name four exogenetic forces.
Answer:
The exogenetic forces are- i. River, ii. Wind, iii. glacier iv. Sea waves.

Answer briefly : 3 Marks

Question 1.
What do you mean by exogenetic processes? Give examples.
Answer:
The word ‘Exogenetic’ comes from the words ‘Exo’ (meaning outside) and ‘Genesis’ (meaning creation). Hence, ‘exogenetic’ refers to forces that are created outside the earth’s surface. The exogenetic processes are controlled by static natural forces (like sun, pressure, humidity, rainfall etc.) and dynamic natural forces (like river, wind, glacier etc.). These processes work for a long time on the surface of the earth, create new sculptures and gradually change the present landforms.

Question 2.
What are the characteristics of exogenetic processes?
Answer:
The characteristics of exogenetic processes are :
i. These are slow processes.
ii. They change the current landforms.
iii. They occur by the agents like river, wind, glacier, sea waves, ground water, tides etc.
iv. These are very time consuming processes.
v. By these processes, some landforms are lowered while some landforms gain height.
vi. Landforms are changed into smooth graded profiles.
vii. The sun and the atmosphere are the main sources of energy.
viii. Slope plays an important role.

Question 3.
Describe briefly the exogenetic processes of landform creation.
Answer:
i. Degradation: The processes which result in lowering the height of high landforms are called degradation processes.
Result : The primary landforms (mountains, hills, plateaus etc.) are transformed into secondary landforms.
Processes: Weathering, mass wasting, erosion.

ii. Aggradation : The processes which result in increasing the height of landforms by filling up of lowlands, basins or depressions are called aggradation processes.
Result : Formation of loess, alluvial cones and fans, flood plains, natural levee, delta, moraines, drumlins, out wash plains etc.

iii. Biological processes: The exogenetic processes that create new landforms with the interference of man, animals and plants are called biological processes.

Question 4.
Compare and contrast between weathering and gradation.
Answer:

Topic	Weathering	Gradation
i. Definition	Breaking and fragmentation of rocks and lying in situ.	Attaining of a smooth profile by erosion, transportation and deposition of earth material.
ii. Energy	Static sources of energy like heat, pressure humidity, rainfall etc.	Both static and dynamic sources of energy like river, wind, glacier, sea waves etc.
iii. Source of energy	Solar energy and weather elements.	Static and dynamic natural sources of energy.
iv. Process	Mechanical, chemical and biological weathering.	Degradation, aggradation and biological process.
(v. Nature of process	Static process.	Both static and dynamic.
vi. Movement of materials	Rocks are fragmented but are not moved.	Rocks are fragmented, eroded or moved and deposited elsewhere.
vii. Result	Main process of soil formation	Process of landscape formation and graded land profile.

Question 5.
Compare and contrast between degradation and aggradation.
Answer:

Topic	Degradataion	Aggradation
i. Definition	Process of erosion and removal of earth’s material and reducing the height of original landform.	Process of deposition of eroded material in lowlands and depressions and increasing the height of original landforms.
ii. Process	Weathering, erosion and mass wasting.	Deposition by dynamic natural forces like river, wind, glacier, sea waves etc.
iii. Height	Original height of landform reduces.	Original height of landform increases.
iv. Denudation	Denudation occurs and new surface of landform is exposed.	Original land surface is covered up due to deposition.
v. Landforms	Monadnock, inselberg, mesa, butte, dhand, canyon, blow hole etc.	Loess, alluvial cones and fans, flood plains, delta, moraines etc.

Question 6.
What is the inter-relationship between weathering, erosion and denudation?
Answer:
Weathering is the process by which rock materials are broken and fragmented by different weather elements. These fragmented materials lie in situ and are not moved. Erosion is the process by which the broken and fragmented rock materials are removed from one place to another by the dynamic forces of nature like river, wind, glacier, sea waves etc. Weathering and erosion are inter dependent. Unless weathering occurs, erosion cannot start. Unless erosion removes the rock debris, further weathering cannot occur.
Denudation is the process by which the outer cover of the landform is removed and a new surface comes out. This cannot occur unless weathering and erosion occur. Hence all these processes are inter dependent.

Question 7.
Give a brief description of gradation.
Answer:

The term ‘gradation’ comes from the word ‘grade’. This was first used by G. K. Gilbert in 1876. ‘Gradation’ means ‘to bring in to a common or uniform level land’. The landforms created mainly by the geotectonic forces (mountains, hills, plateaus, plains, etc.) are acted upon by various exogenetic forces (weathering, mass wasting, erosion etc by different agents). These landforms one highered, lowered or smoothened by the process of aggradation or degradation. Thus the forces which help to bring about this action are called gradational forces.

Question 8.
What is the inter relationship between degradation, aggradation and gradation?
Answer:
The processes of degradation and aggradation work hand in hand in case of changing of landscape. Degradation refers to the process of lowering of existing landforms by weathering and erosion of weathered materials. Aggradation refers to the deposition of these eroded materials in depressions and lowlands, thus raising the altitude of the place. Deposition is an evitable outcome of erosion. Hence the processes of degradation and aggradation go hand in hand. The result of aggradation and degradation is lowering and smoothening of high and rugged landforms and raising of lowlands. Thus a graded or uniform landform is formed by the process of gradation. Hence, it is said that gradation cannot occur without aggradation and degradation. All these three processes are inter-related.

Question 9.
Why is the degradation process called a destructive process ?
Answer:
The process by which highlands including high mountains, hills, plateaus are lowered by different erosional process of river, wind, glacial, seawaves and also by masswasting, denudation to achieved a equllibrium position is called degradation. The original heights of the surface forms are eroded and lowered down by degradation.So that, the said process is also called a destructive process.

Answer in details : 5 Marks

Question 1.
Discuss briefly about exogenetic processes of landform creation.
Answer:
[All exogenetic processes have been explained part by part earlier].

Question 2.
Discuss the role of exogenetic processes in creation of landforms.
Answer:
Landforms created by exogenetic processes are mainly formed by degradation or aggradation.
i. Degradation : By this process, the primary landforms like mountains, hills and plateaus are lowered to form secondary landforms.
Landforms : (a) Degradation starts with formation of regolith on the land surface.
(b) High mountains are reduced to plateaus and finally plains.
(c) Plateaus are dissected and finally reduced to plains.
(d) Slope of land reduces and merges with the sea level.
(e) Landforms created are – gorges, canyon, pot holes, waterfalls, plunge pools, interlocking spurs, gour, zeugen, yardang, ventifact, inselberg etc.
ii. Aggradation : By this process, landforms are created by deposition of eroded materials in low lands and depressions.
Landforms : Flood plains, deltas, loess, outwash plains etc.

Question 3.
Discuss the characteristics of exogenetic processes of landform creation.
Answer:
i. Nature : Very slow process except for landslide and flood.
ii. Place : Occurs mostly on the land surface and sub-surface of the earth.
iii. Forces : Weathering, erosion, mass wasting agents along with river, wind, sea waves, glaciers, tides etc.
iv. Processes : (a) Weathering, erosion and deposition of materials by river, glacier, wind, sea waves, ground water etc.
(b) Mass wasting due to gravitational force.
(c) Mechanical, chemical and biological weathering.
v. Result : Reduction of original landmass to simple, plain, smooth landform mostly by reducing height and some depositions.

Question 4.
Discuss the processes of landform creation by exogenetic processes.
Answer:
i. Degradation : The processes which result in lowering the height of high landforms are called degradation processes.
Result : The primary landforms (mountains, hills, plateaus etc.) are transformed into secondary landforms.
Processes : Weathering, mass wasting, erosion.

ii. Aggradation : The processes which result in increasing the height of landforms by filling up of lowlands, basins or depressions are called aggradation processes.
Result : Formation of loess, alluvial cones and fans, flood plains, natural levee, delta, moraines, drumlins, out wash plains etc.

iii. Biological processes : The exogenetic processes that create new landforms with the interference of man, animals and plants are called biological processes.

Question 5.
Discuss the role of aggradation and degradation processes in formation of new landforms.
Answer:
Landforms created by exogenetic processes are mainly formed by degradation or aggradation.
i. Degradation : By this process, the primary landforms like mountains, hills and plateaus are lowered to form secondary landforms.
Landforms : (a) Degradation starts with formation of regolith on the land surface.
(b) High mountains are reduced to plateaus and finally plains.
(c) Plateaus are dissected and finally reduced to plains.
(d) Slope of land reduces and merges with the sea level.
(e) Landforms created are – gorges, canyon, pot holes, waterfalls, plunge pools, interlocking spurs, gour, zeugen, yardang, ventifact, inselberg etc.
ii. Aggradation : By this process, landforms are created by deposition of eroded materials in low lands and depressions.
Landforms : Flood plains, deltas, loess, outwash plains etc.

Question 6.
Discuss the role of the different agents of gradation in formation of new landforms.
Answer:
The various agents of gradation work on the existing landforms created on the surface of the earth and bring about changes in relief. The role of the different agents of gradation are discussed below :

i. River : River is the most powerful agent of gradation. It erodes the valleys and basins through the processes of abrasion, attrition, solution and hydraulic action. The various landforms created due to erosion are-gorge, canyon, waterfall, plunge pool, interlocking spurs etc. The landforms created due to deposition of materials are – alluvial cone, alluvial fan, natural levee, delta, sand bar etc.

ii. Wind : Wind is an effective agent of gradation in arid regions. It erodes through the processes of abrasion, attrition, friction etc. Landforms produced due to wind erosion are – dhand, blow out, inselberg, gour, zeugen, yardang, dreikanter, ventifact etc. Landforms created due to deposition by wind are sand dunes, loess, etc.

iii. Glacier : Glaciers erode in cold regions by the processes of abrasion, attrition and plucking. Landforms created by glacial erosion are – corrie or cirque, pyramid peak, hanging valley, roche moutonnee. Glaciers deposit materials after they melt in warmer regions. Landforms created by glacial depositions are moraines, drumlin, esker, kame, outwash plains etc.

iv. Sea waves : Sea waves erode with the force of the waves by the processes of abrasion, attrition, collision, friction etc., creating landforms like sea escarpments, sea caves, blow holes, pillars, stumps, stacks etc. The depositional landforms created by waves are- gulfs, bays, sand bars, spits, tombolos, beaches etc.

v. Ground water : Ground water generally erodes through a very slow process mainly by solution in limestone regions. Landforms thus created are – sink hole, swallow hole, uvala, polje, terrarosa etc. The materials dissolved in the water may get deposited to form features like stalactite, stalagmite, pillars etc.

vi. Mass wasting : In hilly regions, landslides and mass wasting may reduce height of the hills and mountains.

vii. Others : Sudden occurrence of tsunami, flood etc. also contribute to degrade or aggrade a region.

Question 7.
What are the results of degradation of landforms ?
Answer:
Degradation is the process of reduction of landforms gradually, thus producing newer landforms. The results of degradation are :
i. Creation of regolith on the earth’s surface, which leads to the formation of soil.
ii. High mountains or hills are eroded and lowered to form plateaus. They can be further lowered to form plains.
iii. Rugged plateaus are first dissected by the numerous rivers flowing through them. Later, they are reduced to plains.
iv. Higher plains are further reduced to form lower plains with lesser undulations and minimum slope.
v. The ruggedness of landforms is smoothened and a uniform slope is formed.

Multiple Choice Questions (MCQ) 1 Mark

Question 1.
Landform building processes can be broadly divided into – parts.
(A) 2
(B) 3
(C) 4
(D) 5
Answer:
(A) 2

Question 2.
The exogenic processes are
(A) Sudden
(B) Medium fast
(C) Slow
(D) Very slow
Answer:
(D) Very slow

Question 3.
The term ‘grade’ was first used by-
(A) Thornbury
(B) Morris Davis
(C) Gilbert
(D) Prat
Answer:
(C) Gilbert

Question 4.
Which of these is an exogenic process?
(A) Earthquake
(B) Vulcanism
(C) Sea waves
(D) None of these
Answer:
(C) Sea waves

Question 5.
The process of lowering the height of landforms is
(A) Degradation
(B) Aggradation
(C) Gradation
(D) None of these
Answer:
(A) Degradation

Question 6.
Which of these is an example of aggradation ?
(A) Pot hole
(B) Waterfall
(C) Canyon
(D) Delta
Answer:
(D) Delta

Question 7.
Which exogenic process results in formation of flood plains ?
(A) Aggradation
(B) Degradation
(C) Gradation
(D) Biological weathering
Answer:
(A) Aggradation

Question 8.
What happens to the slope of land due to aggradation ?
(A) Remains same
(B) Becomes nil
(C) Reduces
(D) Increases
Answer:
(C) Reduces

Question 9.
Degradation and aggradation together result in
(A) Erosion
(B) Weathering
(C) Gradation
(D) Mass wasting
Answer:
(C) Gradation

Question 10.
What happens to the slope of land due to degradation ?
(A) Reduces
(B) Increases
(C) Remains static
(D) Becomes zero
Answer:
(A) Reduces

Question 11.
Which one is not a process of degradation?
(A) River erosion
(B) River deposition
(C) Weathering
(D) Mass wasting
Answer:
(B) River deposition

Question 12.
An agent of exogenic process is
(A) Earthquake
(B) Vulcanism
(C) Earth movement
(D) River
Answer:
(D) River

Question 13.
Height of landforms is increased by
(A) Degradation
(B) Aggradation
(C) Weathering
(D) Lands Lide
Answer:
(B) Aggradation

Question 14.
Exogenic processes mainly result in –
(A) Aggradation
(B) Degradation
(C) Aggradation and degradation
(D) None of these
Answer:
(C) Aggradation and degradation

Question 15.
The process that creates a balance between erosion, transportation and deposition is –
(A) Weathering
(B) Mass wasting
(C) Atmospheric process
(D) Gradation
Answer:
(D) Gradation

Question 16.
Gradation results due to-
(A) Erosion
(B) Deposition
(C) Weathering
(D) All of these
Answer:
(D) All of these

Question 17.
A landform created by agradation is –
(A) Fault
(B) Exfoliation
(C) Loess
(D) Mass wasting
Answer:
(C) Loess

Question 18.
The process of increasing height of a landmass is-
(A) Aggradation
(B) Degradation
(C) Continental movements
(D) Orogenic movements
Answer:
(A) Aggradation

Question 19.
Geologists Chamberlen and Salisbury (1904) have remarked exogenic processes as –
(A) Erosion process
(B) Abrasion process
(C) Biological process
(D) Gradation process
Answer:
(D) Gradation process

Question 20.
Heat, air pressure, humidity, river, wind, glacier etc. are agents of –
(A) Endogenic processes
(B) Non-earth processes
(C) Convectional processes
(D) Exogenic processes
Answer:
(D) Exogenic processes

Question 21.
Gradation is a – process.
(A) Atmospheric
(B) Endogenic
(C) Exogenic
(D) Spacial
Answer:
(C) Exogenic

Question 22.
Alluvial plains are created by –
(A) Gradation
(B) Aggradation
(C) Radiation
Weathering
Answer:
(A) Gradation

Question 23.
The work of exogenic processes is –
(A) Constructive
(B) Destructive
(C) Both constructive and destructive
(D) None of these
Answer:
(C) Both constructive and destructive

Question 24.
Source of energy of all exogenic processes is –
(A) Sun
(B) Space
(C) Earth’s magnetic field
(D) Endogenic forces
Answer:
(A) Sun

Question 25.
An important exogenic process is –
(A) Tension
(B) Compression
(C) Expansion
(D) Erosion
Answer:
(D) Erosion

Question 26.
Exogenic processes depend on – forces.
(A) Earth’s interior
(B) Forces working on earth’s surface
(C) Geothermal
(D) Earthquake
Answer:
(B) Forces working on earth’s surface

Question 27.
River, wind, glacier, sea waves, etc. are agents of – processes.
(A) Endogenic
(B) Exogenic
(C) Spacial
(D) None of these
Answer:
(B) Exogenic

Question 28.
An agent of degradation is –
(A) Weathering
(B) Biological action
(C) Gradation
(D) Subduction
Answer:
(A) Weathering

Question 29.
An agent of agradation is –
(A) Tides
(B) Tsunami
(C) Flowing water
(D) Sea waves
Answer:
(C) Flowing water

Question 30.
The process by which the landforms on the earth’s surface tends to reach a balanced profile is called –
(A) Aggradation
(B) Degradation
(C) Subduction
(D) Gradation
Answer:
(D) Gradation

Question 31.
The process by which natural agents reshapes the existing landscapes over the earth’s surface is known as
(A) Exogenetic
(B) Endogenetic
(C) Orogenetic
(D) Epirogenetic process
Answer:
(A) Exogenetic

Question 32.
The process by which the earth surface increases is –
(A) Aggradation
(B) Degradation
(C) Weathering
(D) Denudation
Answer:
(A) Aggradation

Fill in the blanks : 1 Mark

1. The process by which the natural forces create landforms on the earth’s surface are called ________.
2. The sources of energy for exogenic processes apart from gravitation are _______ and ________.
3. The process of aggradation and degradation together result in a _______ profile.
4. The limit of degradation or erosion is marked by the nearest ________.
5. Delta, sand beach, flood plain etc. are examples of _______ process.
6. The main controlling factor of aggradation is ________.
7. The term ‘gradation’ was first used by ________.
8. The process of _______ brings a balance between erosion, transportation and deposition.
9. An example of an endogenetic process of landform formation is ________.
10. The process of modifying landforms by combined action of erosion and weathering called ________.
Answer:
1. Exogenic processes
2. Sun and atmosphere
3. Graded
4. Sea level
5. Aggradation
6. Slope
7. Gilbert
8. Gradation
9. Plate movement
10. Denudation

State True or False : 1 Mark

1. Filling up of lowlands is a process of aggradation or deposition. [ ]
2. Lowering of height of highlands occurs due to degradation. [ ]
3. The main source of energy of exogenic process is the sun. [ ]
4. The main agent of gradation is river. [ ]
5. Loess plains are formed by degradation. [ ]
Answer:
1. T
2. T
3. T
4. T
5. F

Answer in few words : 1 Mark

Question 1.
What are the processes of landform creation known as a whole?
Answer:
Earth movements.

Question 2.
Name an agent of exogenic process.
Answer:
River or glacier or wind.

Question 3.
Which process is responsible for planation or formation of plains on the earth’s surface?
Answer:
Gradation.

Question 4.
What is the result of gradation?
Answer:
Planation of the landform.

Question 5.
Which process of planation results in filling up of river beds and flooding?
Answer:
Aggradation.

Question 6.
Name the processes that cause degradation.
Answer:
Erosion, transportation and mass wasting,

Question 7.
Name the main source of energy for the exogenetic process.
Answer:
Sun.

Question 8.
What is the process of removal of weathered rocks to other places ?
Answer:
Erosion.

Question 9.
What is the process of filling of loose materials like rocks and soil along the slope?
Answer:
Mass wasting.

Question 10.
What type of weathering is most prominent is desert region?
Answer:
Mechanical weathering.

Question 11.
Match the following :
Answer:

A column	B column
1. Endogenetic force	(a). Weathering
2. Exogenetic force	(b). Delta
3. Aggeadation	(c). main source is sun
4. Degradation	(d). Beneath the surface

Practicing with West Bengal Board Class 10 History Book Solutions and WBBSE Class 10 History Sample Question Paper Set 2 alongside detailed explanations can lead to a deeper understanding of the subject.

West Bengal Board Class 10 History Model Question Paper Set 2

Group A

1. Choose the correct answers to the following :

Question 1.
Of the following who wrote his first play Anande Raho in 1882?
a. Jogendra Gupta
b. Giris Chandra Ghosh
c. Dasarathi Roy
d. Sridhar Kathak
Answer:
b Giris Chandra Ghosh

Question 2.
Of the following who authored the book on sports entitled Twenty-two Yards of Freedom?
a. Ramchandra Guha
b. Ashis Nandy
c. Boria Mazumder
d. Niharranjan Roy
Answer:
c. Boria Mazumder

Question 3.
Of the following which was a scholarly writing on architecture ?
a. History of Indian and Eastern Architecture
b. An Imperial vision
c. Silpasashtra
d. Making of a New Indian Art
Answer:
c. Silpasashtra

Question 4.
Of the following who composed a Bengali book on the dry plate photography?
a. Mahim Chandra Thakur
b. Saraccandra Deb
c. Ramendrasundar Trivedi
d. Adisvara Ghatak
Answer:
d. Adisvara Ghatak

Question 5.
Of the following who was not associated with the foundation of the Hindu College?
a. David Hare
c. Iswarchandra Vidyasagar
b. Kaliprasanna Singha
d. Louis Henry Vivian Derozio
Answer:
b. Kaliprasanna Singha

Question 6.
Which of the following Brahmo leaders was called ‘Brahmananda’?
a. Sivnath Shastri
b. Debendranath Tagore
c. Keshab Chandra Sen
d. Radhakanta Deb
Answer:
c. Keshab Chandra Sen

Question 7.
Of the following who was the earliest feminist of modern Bengal ?
a. Sarojini Naidu
b. Padmaja Naidu
c. Swarup Rani
d. Sarala Devi
Answer:
d. Sarala Devi

Question 8.
Of the following who put forward the idea of Sarbadharma Samanyay?
a. Sri Ramakrishna Deva
b. Bijay Krishna Goswamee
c. Swami Vivekananda
d. Lalan Faqir
Answer:
a. Sri Ramakrishna Deva

Question 9.
In which of the following places did the Kol Rebellion take place 1831-32. ?
a. Bengal
b. Rangpur in present Bangladesh
c. Chotonagpur
d. Bhagalpur, in Bihar
Answer:
c. Chotonagpur

Question 10.
Of the following places where did the Bheels enjoy monopoly of power?
a. Chotonagpur
b. Khandesh
c. Andhra region
d. Kerala region
Answer:
b. Khandesh

Question 11.
Of the following who led the Barasat Rebellion?
a. Dudu Mian
b. Titu Mir
c. Joa Bhagat
d. Durjan Singh
Answer:
b. Titumir

Question 12.
Of the following who was the first Governor-General of India ?
a. Lord Dalhousie
b. Lord Canning
c. William Bentinck
d. Warren Hastings
Answer:
c. William Bentinck

Question 13.
In which stage of the national movement did the Eka Movement take place?
a. Quit India Movement
b. Civil Disobedience Movement
c. Non-Cooperation Movement
d. Partition of Bengal
Answer:
c. Non-Cooperation Movement

Question 14.
In which of the following years did the All India trade Union Congress come into existence?
a. 1905
b. 1917
c. 1919
d. 1920
Answer:
d. 1920

Question 15.
The Workers’ and Peasants’ Party was associated with which of the following?
a. Rowlatt Satyagraha
b. Working class movement
9. Non-Cooperation Movement
d. Bardoli Satyagraha
Answer:
b. Working class Movement

Question 16.
Of the following who was associated with the Civil Disobedience Movement ?
a. Kalpana Dutta
b. Kamaladevi Chattopadhyay
c. Bina Das
d. Pritilata Waddedar
Answer:
b. Kamaladevi Chattopadhyay

Question 17.
Of the following who led the Chittagong Armoury raid ?
a. Binoy Bose
b. Dinesh Gupta
c. Masterda
d. Rashbehari Bose
Answer:
c. Masterda

Question 18.
Of the following who first coined the term harijan to describe the dalits ?
a. B. R. Ambedkar
b. Mahatma Gandhi
c. Jogendranath Mondal
d. Narasimha Mehta
Answer:
d. Narasimha Mehta

Question 19.
Of the following who tried to unite the Namasudras in their struggle against exploitation?
a. Haridas Thakur
b. Harichand Thakur
c. Guruchand Tahakur
d. None of the above
Answer:
b. Harichand Thakur

Question 20.
Of the following who was the chairman of the States Reorganization Committee formed in 1953 ?
a. K.M. Panikkar
b. Abul Kalam Azad
c. Fazl Ali
d. Vallabhbhai Patel
Answer:
c. Fazl Ali

Group B.

2. Answer the following Questions.

Attempt one question from each sub-group: In all 16 questions 1×16=16

Answer each of the following questions in one sentence :

Question 1.
Who was the author of the autobiography Jibaner Jharapata?
Answer:
Sarala Devi Chaudhurani’s autobiography is known as Jibaner Jharapata.

Question 2.
Who was the editor of the journal Grambarta Prakashika?
Answer:
Kangal Harinath Majumdar was the editor of the popular journal named Grambarta Prakashika

Question 3.
In which year was the Bethune Female School established?
Answer:
The Bethune Female School was established in 1849.

Question 4.
Who was the first Indian woman to become the President of the Congress?
Answer:
The first Indian to become the President of the Indian National Congress was Smt. Sarojini Naidu.

Identify which of the following is ‘True’ or ‘False’ :

Question 1. Rammohan Roy was associated with the Hindu widow re-marriage.
Answer: False

Question 2. Hindoo Patriot was English weekly published from Kolkata.
Answer: True

Question 3. The Science College was founded with aid from the British govt.
Answer: False

Question 4. Bardoli Satyagraha was the first civil disobedience movement of the peasantry of Bardoli in Surat.
Answer: True

Match column ‘A’ with column ‘B’

A	B
1. Bengali periodical that gave emphasis to women issues	(a) Neel Darpan
2. Harish Chandra Mukherjee	(b) Bamabodhini
3. Oppressions of the indigo planters	(c) Hutum Pyanchar Naksha
4. Description of a Kolkata city street	(d) Hindoo Patriot

Answer:
1-b, 2-d, 3-a, 4 -c

Identify the following places in the given map of India :

1. The area of Sannyasi-fakir Revolt.
2. Areas of the Indigo Revolt of Bengal.
3. Centre of Rangpur (in Bangladesh) Revolt.
4. Centre of the Chuar Rebellion.
Answer:
See the attached Map of India
Or
(Only for blind students

Fill in the blanks with right words :

1. The Act that laid the foundation of education in India was …………………..
Answer:  Charter Act of 1813

2. Jibaner Jharapata was an autobiography of …………………..
Answer: Sarala Devi Chaudhurani

3. The students of Derozio together was known as …………………..
Answer:  Young Bengal

4. ………………….. was associated with the Hindu Mela.
Answer: Rajnarain Bose

Select the correct interpretation of the following statements :

1. Statement: Rammohan Roy strongly advocated for introduction of Western education.

Interpretation 1: Rammohan was opposed to setting up of Sanskrit College
Interpretation 2: No real education was possible without a knowledge of Western science and philosophy.
Interpretation 3: Rammohan was the founder of the Anglo-Hindu School.
Answer:
Interpretation 2: No real education was possible without a knowledge of Western science and philosophy.

2. Statement: Anandamath was a novel written by Bankin Chandra Chatterjee.

Interpretation 1: Anandamath became the gospel of Indian revolutionaries.
Interpretation 2: This was the first literary journal of its kind.
Interpretation 3: This published articles on economic issues
Answer:
Interpretation 1: Anandamath became the gospel of Indian revolutionaries.

3. The Baptist Mission Press started printing Bengali books.

Interpretation 1: The Press was first of its kind in Bengal.
Interpretation 2: The Press facilitated assimilation of Eastern and Western cultures in the country.
Interpretation 3: The Press supplied books to the trainees of Fort William College.
Answer:
Interpretation 2: The Press facilitated assimilation of Eastern and Western cultures in the country.

4. The Anti-Circular Society was organized in 1905.

Interpretation 1: It provided education to the students who were ousted from the government schools.
Interpretation 2: The Society encouraged the students to participate in the political movement.
Interpretation 3: The Society helped to educate the Working class.
Answer:
Interpretation 1: It provided education to the students who were ousted from the government schools.

Group C.

Answer the following questions in 2 or 3 sentences (any 11)

Question 1.
Would you say the music has been an integral part of Indian culture ?
Answer:
Indeed, music has been an integral part of the Indian culture. Since the time of the Vedas music is being practiced. The oldest preserved example of Indian music is to be sound in the Samaveda of the Vedic corpus.

Question 2.
How would you define ‘New Social History?
Answer:
‘New Social History’ or simply ‘social history’ is a branch of history that studies the experiences of common people. The New Social History emerged through the writings of British historians like Edward Thomson, Eric Hobsbawm, etc.

Question 3.
How would you explain ‘fashion’?
Answer:
‘Fashion’ may be defined as a popular style or practice particularly in clothing. It changes from time to time.

Question 4.
Why is government document important source of history ?
Answer:
Reports, intelligence reports, police reports, etc. may be regarded as government documents which constitute primary materials. Interpretation and analysis, etc. of such documents are the secondary documents.

Question 5.
Why was Bamabodhini periodical important ?
Answer:
Bamabodhini, a monthly journal edited by Umesh Chandra Dutta, was published in 1863. The journal greatly influenced the womenfolk in many ways, especially about their rights. Many women entered literary career through writing in Bamabodhini.

Question 6.
Who was John Elliot Drinkwater Bethune?
Answer:
Until Bethune’s arrival in India, the East India Company took little initiative to introduce female education in the country. As Bethune was aware of the suffering and deprivation of women in this country, he was eager to impart formal education to the girls.

Question 7.
How did Keshab Chandra Sen infuse new blood to the Brahmo Samaj ?
Answer:
Keshab Chandra infused new blood to the Brahmo Samaj as he included programme of social reform alongside missionary activities of the Samaj. Keshab Chandra also undertook welfare measures for the people in distress.

Question 8.
What is an ‘uprising’?
Answer:
An uprising may be defined as a protest organized locally against authority or certain governmental policy. There is little difference between rebellion and uprising.

Question 9.
Who were the Bheels ?
Answer:
Bheels were a section of the backward and warlike community of central India. They resorted to plunder and loot of rich landholders in their vicinity. Their plunder seriously affected the law and order of Khandesh.

Question 10.
What do you understand by the term ‘Age of Associations’?
Answer:
In the absence of political parties the associations used to play the role of representing the opinion of the people everywhere in the world. In India as well it was through the political associations of the nineteenth century that India entered into the arena of modern politics. Thus the ‘Age of Associations’ was crucial to the development of the country when a good number of political associations came to be established.

Question 11.
Write in short about the Eka Movement.
Answer:
During the period of the Non-Cooperation movement some insurgent peasants of United Province were active under the name Eka. The rebel peasants took the vow that they would pay only the recorded rent, and under any circumstances hey would not leave their land.

Question 12.
Write in short about the Indian Independence League.
Answer:
In 1928 the Indian Independence League was formed jointly by Jawaharlal Nehru and Subhas Chandra Bose. The Organization pressurized the Congress and Gandhiji to start movement for the attainment of Complete Independence (Poorna Swaraj).

Question 13.
How did the students participate in the Civil Disobedience movement ?
Answer:
With the outbreak of the Civil Disobedience Movement, the student community of Bengal became a formidable force. Between 1930 and 1933 as many as fifteen thousand students were imprisoned by the British on the charge of violating Section 144 or for picketing in front of business establishments.

Question 14.
Who was Jotiba Phule?
Answer:
A social reformer of Maharashtra, Jotiba Phule was pioneer in establishing a girls’ school at Poona (Pune) in 1851. The reform movement received further impetus when an organization named Paramhansa Mandali launched movement for breaking the caste rules and untouchability. Jotiba Phule also launched a fierce movement against the supremacy of Brahmmins in the Hindu society.

Question 15.
How was Junagadh acceded to the Indian Union?
Answer:
Muhammad Muhabay Khanji III, the ruling Nawab of Junagadh, declared accession to Pakistan. As a protest against this the people of Junagadh launched a fierce movement. In November 1947 the Government of India took over the administration at the express desire of the people of Junagadh.

Group D.

4. Answer the following questions in 7/8 sentences :

(Attempt one question from each sub-group: in all 6 questions)

Question 1.
Write how did Dinabandhu Mitra raise his voice against the oppressions of the indigo planters.
Answer:
The indigo rebellion of Bengal constituted an important chapter in the history of peasant movement in India during the British colonial rule. The most important aspect of the indigo rebellion was the support lent for the first time by the educated middle class to the rebel peasantry. Dinabandhu’s native home Jessore was one of the main centres of indigo cultivation.

Thus he had first-hand knowledge of how the indigo planters used to oppress the peasantry. In the play Neel Darpan Dinabandhu exposed the grim picture of inhuman villainy and torture perpetrated by the indigo planters. It was due to the efforts of Dinabandhu Mitra that the Bengali middle class came out in open support to the indigo rebels.

Question 2.
What were the contributions of Debendranath to the Brahmo Movement?
Answer:
After the death of Rammohan Roy the cause of Brahmo Movement was taken up by Debendranath Tagore. He infused a new life into the Brahmo movement. He founded the Tattwabodhini Sabha in 1839 that took over the charge of the Brahmo Samaj.

In fact, the credit of transforming the Brahmo Samaj into a distinctive religious order belongs to Debendranath Tagore. With a view to disseminating the doctrine of Brahmoism amongst the people Debendranath brought out the first number of Tattwabodhini Patrika in 1843. Later on, under the leadership of Keshab Chandra Sen the Brahmo Samaj emerged as the leading social organization of India.

Question 3.
What was the nature of the Revolt of 1857 ?
Answer:
The nature of the Revolt of 1857 is a very contentious issue, and debate over it started from the very moment of its happening.

a. Opinions are sharply divided as to whether the Revolt of 1857 was mere a mutiny or a War of Independence.

b. Considered from the nature of the rising the old school of historians found it difficult to call it a War of Independence on the following grounds

• There was no definite political ideal before the rebels. Though expulsion of the British was the immediate goal, there was no co-ordinated plan to establish an independent government in place of the British.
• There was no plan, no co-ordination among the rebels in different parts of the country. The fact that at least some of the zamindars and talukdars (landed magnates) participated in the rebellion would at best give it a feudal character as Jawaharlal Nehru pointed out.
• Common people did not participate in any measure that can legitimately give it the name of a ‘national rising’.

c. Professor S. N. Sen in his book entitled Eighteen Fifty-seven concluded that the mutiny of 1857 was not simply a rising of the sepoys. He argued that a national rising does not require participation of all people. Only an influential section of people had participated in the revolutions of France and America. On such arguments Professor Sen calls it a ‘national rising’, although to a limited extent.

Question 4.
How did the Calcutta Science College develop?
Answer:
The University College of Science and Technology is also known as the Rajabazar Science College. Officially, however, it is known as the Rashbehari Siksha Prangan. This is one of the four campuses the University of Calcutta has in Kolkata. The Science College was founded in 1914 by the then legendary Sri Asutosh Mukherjee, the then Vice-Chancellor of the University of Calcutta.

The Science College was founded without any aid from the colonial British government in India. In fact, establishment of this science division of the University of Calcutta was possible due to the generous donation of about thirty-seven and half lacs of rupees made by Sri Rashbehari Ghosh and Sri Taraknath Palit together.

The Rajabazar Science College has been officially named Rashbehari Siksha Prangan in memory of Sri Rashbehari Ghosh, and the Ballygunge Science College is named Taraknath Siksha Prangan. The first batch of teachers included Acharya Prafulla Chandra Roy, the Nobel laureate Sir Chandra Sekhar Venkata Raman, popularly known as ‘C. V. Raman’, Sisir Kumar Mitra, etc. The legendary 1915 M.Sc. batch comprised Satyendranath Bose, Meghnad Saha, Jnanchandra Ghosh and others.

Question 5.
How did printing press help the spread of education ?
Answer:
During the 18-19 centuries people in India were largely illiterate and would remain so for many centuries. But some educated enlightened Indians and a small number of professional people who lived and worked in towns, however, felt the need of books.

In India in the past, like many Western countries, copyists multiplied books by hand. But with the introduction of printing text books of all sorts, English and vernacular, grammars, elementary books were published that catered to the needs of the people.

In fact, printed books became a medium for the dissemination of knowledge. The elementary Bengali text book that deserves mention for the learning of Bengali language is that of Varna Parichay by Iswarchandra Vidyasagar. However, how printing helped dissemination of knowledge may be explained with an example.

The Baptist Mission and its Press printed and published text-books, religious books and other works in vernacular languages, and in English. Books translated from English to Bengali also included in the list of publications. All this facilitated spread of education.

Question 6.
How did the Indian peasantry participate in the anti-Partition Movement ?
Answer:
A significant event in the early years of Indian national movement, particularly in Bengal, was the anti-Partition agitation. The announcement of partition set off a mighty upsurge. The anti-partition movement soon assumed an all-India character in which different classes of people participated. Despite the popular character of the anti-partition movement it must be admitted that it was largely confined to the urban middle class.

• The peasants’ participation was very much limited. Indeed, the Congress leadership did call upon the peasants to start a no-rent campaign. However, the participation of peasants in the movement was significant at least in some parts of the country.
• The indigo peasants of Champaran in Bihar rose in rebellion. Peasants’ disturbances took place in Assam and Mymensingh (in present Bangladesh).
• The Muslim peasants of Barisal (in present Bangladesh) were led by Aswini Kumar Datta. The Left politics did not emerge in India during the anti-Partition movement. As such there was no question of the Leftists’ leadership amongst the peasants.

Question 7.
How did the socialist influence strengthen the working class movement ?
Answer:
Socialist influences in Indian politics between 1921 and 1924 definitely strengthened the working class movement. Various socialist and communist groups that had emerged in different places were also engaged in organizing labour movements. Despite British Government’s action restraining the activities of the communists the Workers’ and Peasants’ Party (WPP) was formed in 1927. The initiative was taken by the communist leaders like S.A. Dange, Muzaffar Ahmed, P.C. Joshi and Sohan Singh Josh.

The shortlived WPP rapidly spread its organization in the provincial and national levels. Another aspect of the WPP was that it functioned as a left-wing within the Congress. The WPP devoted itself, among other things, to the growth of class consciousness amongst the working class.

The objective of the WPP was to strive for a broad anti-imperialist front for the achievement of complete independence with the ultimate aim of establishment of socialism in the independent country. Though the WPP was short-lived, its units in some of the provinces emerged as the political party of the working class.

Question 8.
What was the part played by women in the Civil Disobedience Movement ?
Answer:
The Non Co-operation Movement was suspended by Gandhiji in 1922. But its suspension found its stronger follow-up in the Civil Disobedience Movement (1930). Participation of women in the Civil Disobedience constituted an important chapter in the history of women’s struggle in the freedom movement.

• Between 1930 and 1932 women in many places played an important role as they conducted picketing in front of the shops selling foreign goods.
• Women’s participation in the Movement, however, took various forms. While Parsee and Christian women residing in Bombay advocated female education, the Gujarati women, under the influence of Gandhiji, aimed at the attainment of Swaraj and women’s freedom.
• In Bengal, women leaders like Kumudini Bose, Latika Ghosh and Hemalata Tagore made sincere efforts promoting women’s welfare and training of women in some useful crafts.
• In U.P. Swarup Rani Nehru, Jawaharlal Nehru’s mother, burdened with age did not hesitate to vote for khadi in the streets. Thus Gandhiji’s Civil Disobedience found wonderful response from the Indian womenfolk.

Group E.

5. Answer any one question in 15/16 sentences :

Question 1.
Write about the spread of Western education under Indian initiative.
Answer:
The introduction of Western education was undoubtedly one of the main factors that caused the Indian awakening.
a. Raja Rammohan Roy : Raja Rammohan Roy was the first Indian to feel the need for Western education, and as such came to be known as the ‘first Modern Man of India’.

• Besides being an indirect supporter of the Hindu College Rammohan was the founder of the Anglo-Hindu School in 1822. In the school Western science, philosophy and literature were taught.
• Rammohan sent a memorial (petition) in 1823 to Lord Amherst advocating for the introduction of Western education in India.Communist Party of India and the communists were isolated from the peasants and workers.

b. Raja Radhakanta Deb: Though out and out a conservative Raja Radhakanta Dev was a promoter of English education and science. Radhakanta had deep respect for Tom Paine’s Age of Reason, which was the Bible of the Derozians. Aware of the importance of the study of science Radhakanta contributed liberally to the fund raiser for sending Indian youths to England for higher studies in medicine and surgery.

c. Other Initiatives : While missionaries were busy organizing English schools the Indians were not sitting idle. They founded a number of schools in Calcutta. The most popular amongst such schools was the Oriental Seminary founded by Gour Mohan Addy. Another English school of repute was the Arpooly Pathsala (Indian Awakenning and Bengal : p 108: Nemai Sadhan Bose).

After 1835 the number of English schools began to increase rapidly. Among the many new institutions opened was the Hooghly College founded in 1836. For this institution Haji Mohammad Mohsin’s property provided a princely donation. This college did much for the spread of English education, particularly among the Muslims. The above is in short the English institutions set up under Indian initiative.

Question 2.
What was the nature of participation of the Communist Party in the Indian national movement ?
Answer:
From the very beginning the Communist Party’s main form of political work was to organize peasants and workers and to work through them.

a. During the 20s of the twentieth century the communist organizers set up unions and organized strikes in India’s textile, jute and cotton mills, and in the railway workshops. But the greatest success was the strike for over six months by the Communist-led Girni Kamgar Union in 1928. Such successes, however, were short-lived.

b. The Meerut Conspiracy Case (1929) gave a severe blow to the activities of the communists. But the communists inflicted a deadly blow on themselves by breaking their connection with the Congress. The communist movement, however, was saved as many of the communists refused to stand apart from the Civil Disobedience Movement and actively participated in it.

c. There was a radical change in the situation in 1935 when the communists once again participated in the activities of the Congress.

d. The communists did not participate in the Quit India Movement. It has been pointed out by Professor Satyabrata Rai Chowdhuri that the Indian communists made mistake as regards national policy of the country.

e. In reconciling the events at home with the international communist movement they were accustomed to look to the (erstwhile) Soviet Union rather than the potentialities of the Indian national movement. However, after Hitler had invaded the Soviet Union in 1941 the Indian communists following the Peoples’ War line suspended all sorts of anti-Imperialist activities lest that would weaken the antifascist war efforts.

f. In the thesis the question of India’s independence was subordinated to the victory of the Soviet Union in the World War II. But this was an unreal expectation because the people of India wanted first to become independent with or without the victory of the Soviet Union. This line certainly isolated and discredited the

Question 3.
How did womenfolk participate in the Quit India Movement? What was the nature of women’s role in the armed revolutionary struggle ? 5+3
Answer:
a. Participation of Women in the Quit India Movement : Women’s participation in the Quit India Movement took various forms in rural and urban areas of the country. While in the rural areas the peasant women protested against prevalent land-system in city areas the message of fight for freedom was propagated through radio transmitter.

• In the rural areas the peasant women joined the men in lodging protest against the hike in land-revenue and other taxes imposed illegally. Also the women protested against the landholders’ rights.
• In Midnapur district of West Bengal, during the course of the Quit India Movement, the peasants attacked the police stations, even the communication network was disrupted by destroying telegraph lines.
• The incident that immortalized Midnapur in the history of the freedom movement was the lead given by Srimati Matangini Hazra, a 73-year-old widow in capturing the court and the police station of Tamluk.
• Usha Mehta, a patriot to the very core of her heart, set up a radio transmitter, known as the Vice of Freedom. Her intention was to circulate the information of war of freedom amongst the people of the country. Usha persisted with her task of broadcasting until she was arrested by the British police (12 November 1942) on the charge of sedition.

b. Nature of Women’s Role in the Armed RevolutionaryStruggle: In the revolutionary struggle participation of women presented a different picture than that of nonviolent struggle.

(i) Women’s involvement in the non-violent struggle had the support and encouragement of Gandhiji. But the women who participated in the armed struggle joined it on their own. That is to say, there had been no encouragement from any quarter to enthuse the women to join the revolutionary struggle.

(ii) In fact, the revolutionary secret societies made no concerted efforts to encourage the participation of women as Mahatma Gandhi had done in regard to the nonviolent activities.

(iii) Another important point to be noted is that direct participation of women in the revolutionary movement was not feasible also due to certain constraints. First, women were not allowed by their male relatives to join the revolutionary secret societies. Second, the risk was too high to allow women to participate in revolutionary feats on an equal basis with men.

(iv) However, in general the indirect participation of women helped the revolutionaries silently from the background. In the above context the revolutionary activities of Pritilata Waddedar and Kalpana Datta may be discussed.

Group F.

6. Answer the questions in a complete sentence

Question 1.
Which Act marked the beginning of Western education in India ?
Answer:
Macaulay’s Minute of 1835 marked the beginning of Western education in India.

Question 2.
Who was the founder of the Brahmo Samaj ?
Answer:
Rammohan Roy was the founder of the Brahmo Samaj

Question 3.
By which Act was the Remarriage of Hindu Widow made legal ?
Answer:
By Act XV Hindu Widow Remarriage was declared legal.

Question 4.
Who were the leaders of the Santal Rebellion of 1855 ?
Answer:
Kanu-Sidhu were the leaders of the Santal Rebellion of 1855

Question 5.
Which was the first linguistically organized state of India ?
Answer:
Hyderabad was the first linguistically organized state of India

7. Answer the following questions in 2/3 sentences :

Question1.
What do understand by the term ‘Local History’ ?
Answer:
Local History is a micro-level study that discloses historical episodes in particular local areas. In this regard mention may be made of Nikhilnath Roy’s Murshidabad Kahini, Kumudnath Mallick’s Nadiya Kahini, etc.

Question 2.
Which was the first association of India with political outlook ?
Answer:
Bangabhasa Prakashika Sabha is regarded as the first political association of India. Details about the activities of the Sabha are not known. But its meeting used to be held in every Thursday where political and other matters of public interest were discussed.

Question 3.
Why is Mangal Pandey important?
Answer:
In the Revolt of 1857 the first shot was fired at Barrackpore when Mangal Pandey shot at a European officer on 29 March 1857. Mangal Pandey along with some others were arrested and hanged after some time. Mangal Pandey is thus remembered for his heroic feat.

Question 4.
Why is Bina Das remembered?
Answer:
Bina Das joined Bhupal Bose’s revolutionary group in 1929. She is remembered as she made an attempt on the life of Stanley Jackson, the then Governor of Bengal. Bina’s action encouraged the youth of Bengal and it was very effective in awakening in them a deep sense of patriotism.