DRAINAGE-CLASS-9-SST-QUESTION ANSWERS

 

Chapter 3 - Drainage Class 9 Subject Social Science (Geography)

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1. Choose the right answer from the four alternatives given below.

(i) In which of the following states is the Wular lake located?

(a) Rajasthan               (c) Punjab

(b) Uttar Pradesh       (d) Jammu and Kashmir

(ii) The river Narmada has its source at ..............

(a) Satpura              (c) Amarkantak

(b) Brahmagiri       (d) Slopes of the Western Ghats

(iii) Which one of the following lakes is a salt water lake?

(a) Sambhar            (c) Wular

(b) Dal                   (d) Gobind Sagar

(iv) Which one of the following is the longest river of the Peninsular India?

(a) Narmada         (c) Godavari

(b) Krishna          (d) Mahanadi

(v) Which one amongst the following rivers flows through a rift valley?

(a) Mahanadi                     (c) Krishna

(b) Tungabhadra               (d) Tapi

Q1. What is meant by the water divide? Give an example.

Answer:  Any elevated area, such as a mountain or upland, separates two drainage basins. Such upland is known as the water divide. Ambala is located on the water divide between the Indus and the Ganga river systems.

2. Answer the following questions briefly.

(i) What is meant by a water divide? Give an example.

Answer: 

• A water divide is a highland or upland area that separates two river systems.

• Example: Ambala is a water divide between the Indus and Ganga river systems.

(ii) Which is the largest river basin in India?

Answer: The Ganga river basin is the largest in India.

(iii) Where do the rivers Indus and Ganga have their origin?

Answer: 

• Indus originates in Tibet, near Lake Mansarovar.

• Ganga originates from Gangotri Glacier in Uttarakhand (as Bhagirathi).

(iv) Name the two headstreams of the Ganga. Where do they meet to form the Ganga?

Answer: 

• Bhagirathi and Alaknanda are the two headstreams.

• They meet at Devprayag in Uttarakhand to form the Ganga.

(v) Why does the Brahmaputra in its Tibetan part have less silt, despite a longer course?

Answer: 

• Tibet is a cold and dry region, so there is less rainfall.

• As a result, the river carries less water and silt in that part.

(vi) Which two Peninsular rivers flow through trough?

Answer: Narmada and Tapi flow through rift valleys or troughs.

(vii) State some economic benefits of rivers and lakes.

Answer: 

• Provide water for irrigation and farming.

• Used for hydroelectric power generation.

• Help in transport and navigation.

• Support fishing and tourism.

• Help control floods and provide drinking water.

3. Below are given names of a few lakes of India. Group them under two categories – natural and created by human beings.

Answer: 

Natural Lakes:

• Wular

• Dal

• Nainital

• Bhimtal

• Loktak

• Barapani

• Chilika

• Sambhar

• Pulicat

Man-made (Artificial) Lakes:

• Gobind Sagar

• Rana Pratap Sagar

• Nizam Sagar

• Nagarjuna Sagar

• Hirakund

4. Discuss the significant difference between the Himalayan and the Peninsular rivers.

Answer: 

1. Origin: Himalayan rivers originate from glaciers and snow, Peninsular rivers mostly from Western Ghats or plateaus.

2. Water flow: Himalayan rivers are perennial, Peninsular rivers are mostly seasonal.

3. Length: Himalayan rivers are longer, Peninsular rivers are shorter.

4. Landforms: Himalayan rivers form gorges, meanders, deltas, etc., Peninsular rivers have fewer landforms.

5. Tributaries: Himalayan rivers have more tributaries, Peninsular rivers have fewer.

5. Compare the east flowing and the west flowing rivers of the Peninsular plateau.

Answer: 

East Flowing Rivers	West Flowing Rivers
Flow into Bay of Bengal	Flow into Arabian Sea
Form deltas at mouth	Form estuaries
Carry more sediments	Carry less sediments
Example: Godavari, Mahanadi, Krishna	Example: Narmada, Tapi
Longer course	Shorter course

6. Why are rivers important for the country’s economy?

Answer: 

1. Rivers provide fresh water for drinking and daily use.

2. Used for irrigation, which supports farming.

3. Help generate hydroelectric power (electricity).

4. Support transportation and trade by boat or ship.

5. Help in fishing, tourism, and developing cities.

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Important Quesions Answer:

 1. What is the role of rivers in shaping the land?

Answer:

1. Rivers erode, transport, and deposit soil and rocks.

2. In hilly areas, rivers form gorges and waterfalls (e.g., Narmada’s Dhuandhar falls).

3. In plains, they create meanders, floodplains, and oxbow lakes.

4. Near the sea, rivers form deltas by depositing silt (e.g., Ganga-Brahmaputra delta).

5. Over time, rivers shape valleys, plains, and coastal landforms.

 2. Write a short note on the Ganga River System.

Answer:

1. Ganga originates as Bhagirathi from the Gangotri glacier in Uttarakhand.

2. Joined by Alaknanda at Devprayag, then called Ganga.

3. Major tributaries: Yamuna, Ghaghara, Gandak, Kosi (from Himalayas), Chambal, Betwa, Son (from Peninsula).

4. Flows through Uttarakhand, UP, Bihar, West Bengal, and into Bangladesh.

5. Forms the Sundarbans Delta, the largest in the world.

 3. Why do rivers cause floods? What are their effects?

Answer:

1. Heavy rainfall or melting glaciers increase river water suddenly.

2. Rivers overflow their banks and flood nearby areas.

3. Floods destroy crops, homes, roads, and kill people and animals.

4. They also spread diseases and pollute water.

5. However, they also replenish soil fertility by spreading rich silt.

 4. How are lakes useful to human beings?

Answer:

1. Provide drinking water and water for irrigation.

2. Help in flood control by storing excess rainwater.

3. Support fisheries and aquaculture.

4. Are centers of tourism and recreation (e.g., Dal Lake, Nainital).

5. Used to generate hydroelectric power in dam-based lakes (e.g., Gobind Sagar).

 5. Write a note on the Brahmaputra River System.

Answer:

1. Originates in Tibet (as Tsang Po), east of Mansarovar Lake.

2. Takes a U-turn at Namcha Barwa, enters India as Dihang.

3. Joins with Dibang, Lohit, and other rivers in Assam and becomes Brahmaputra.

4. Carries more water and silt in India due to high rainfall.

5. Causes frequent floods and forms riverine islands like Majuli, the world’s largest.

 6. What are the causes of river pollution in India?

Answer:

1. Industrial waste is dumped into rivers without treatment.

2. Sewage and domestic waste from cities enters rivers.

3. Excessive use of chemical fertilizers and pesticides in farms.

4. Religious and cultural activities, like immersing idols, flowers, etc.

5. Leads to dead fish, unsafe drinking water, and health problems.

7. Describe the Godavari river system.

Answer:

1. The longest Peninsular river (about 1500 km), called Dakshin Ganga.

2. Originates from Nashik in Maharashtra, flows into Bay of Bengal.

3. Has the largest basin among peninsular rivers.

4. Major tributaries: Purna, Pranhita, Manjra, Wainganga, Penganga.

5. Basin covers Maharashtra, Telangana, Andhra Pradesh, Chhattisgarh, Odisha.

8. What measures can be taken to conserve rivers?

Answer:

1. Reduce industrial and domestic waste dumping into rivers.

2. Build sewage treatment plants in all cities.

3. Promote organic farming and reduce chemical use.

4. Launch awareness campaigns and river-cleaning drives (e.g., Namami Gange).

5. Involve citizens and schools in conservation efforts.

9. Compare the east-flowing and the west-flowing rivers of the Peninsular plateau.

Answer:

East Flowing Rivers:	West Flowing Rivers:
These rivers drain in the bay of Bengal.	These rivers drain in the Arabian sea.
These rivers make deltas in their mouth.	These rivers enter the sea through eastuaries.
These rivers have a developed tributary system. Their tributaries are comparatively large in size.	These rivers are devoid of developed tributary system. Their tributaries are small in size.
These rivers flows through not very deep channels.	These rivers flow in a trough are a funnel like narrow but deep channels.
The Mahanadi , the Godavari , the Krishna, the Kaveri are the main east flowing rivers.	The Narmada and Tapi are main west flowing rivers.

                       

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For More Questions Click Below:

Class 9-History

Chapter 1- The French Revolution

Chapter 2- Socialism in Europe and the Russian Revolution

Chapter 3- Nazism and the Rise of Hitler

Chapter 4- Forest Society and Colonialism

Chapter 5- Pastoralists in the Modern World

Class 9- Civics

Cahpter 1- What is Democracy? Why Democracy?

Chapter 2- Constitutional Design

Chapter 3- Electoral Politics

Chapter 4- Working of Institutions

Class 9- Economics

Chapter 1- The Story of Village Palampur

Chapter 2- People as Resource

Chapter 3- Poverty as a Challenge

Chapter 4- Food Security in India

Class 9- Geography

Chapter 1- India: Size and Location

Chapter 2- Physical Features of India

Chapter 3- Drainage

Chapter 4- Climate

Chapter 5- Natural Vegetation and Wildlife

Chapter 6- Population