NCERT Solutions for Class 9 Geography Chapter 3 Drainage contains answers to the exercise questions given in ‘Contemporary India’. These solutions will help students for the preparation of CBSE Class 9 SST exam. All the answers are useful for exams as most of the questions are asked from the NCERT textbooks. So, students can study these solutions and score high in their exams.
Class 9 Geography Chapter 3 Drainage Questions and Answers
Question 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
(b) Uttar Pradesh
(c) Punjab
(d) Jammu and Kashmir
Answer: (d) Jammu and Kashmir
(ii) The river Narmada has its source at
(a) Satpura
(b) Brahmagiri
(c) Amarkantak
(d) Slopes of the Western Ghats
Answer: (c) Amarkantak
(iii) Which one of the following lakes is a salt water lake?
(a) Sambhar
(b) Dal
(c) Wular
(d) Gobind Sagar
Answer: (a) Sambhar
(iv) Which one of the following is the longest river of the Peninsular India?
(a) Narmada
(b) Krishna
(c) Godavari
(d) Mahanadi
Answer: (c) Godavari
(v) Which one amongst the following rivers flows through a rift valley?
(a) Mahanadi
(b) Tungabhadra
(c) Krishna
(d) Tapi
Answer: (d) Tapi
Question 2: Answer the following questions briefly.
(i) What is meant by a water divide? Give an example.
Answer: A water divide, as described in the provided document, is an elevated area such as a mountain or an upland that separates two drainage basins. An example of water divide is the Western Ghats.
(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: The Indus River has its origin in Tibet near the Mansarovar Lake while the Ganga River has its origin in Gangotri Glacier in Uttarakhand.
(iv) Name the two headstreams of the Ganga. Where do they meet to form the Ganga?
Answer: Alaknanda and Bhagirathi are the two headstreams of the Ganga. They both meet to form the Ganga at Devprayag.
(v) Why does the Brahmaputra in its Tibetan part have less silt, despite a longer course?
Answer: The Brahmaputra carries less silt in its Tibetan part despite a longer course because it flows through a cold and dry region in Tibet. In such environments, there is less erosion and less material available to be picked up and transported by the river. This results in the river carrying a smaller volume of water and less silt in its upper reaches through Tibet.
(vi) Which two Peninsular rivers flow through trough?
Answer: The two rivers that flow through troughs are Narmada and Tapi.
(vii) State some economic benefits of rivers and lakes.
Answer: Rivers have been of fundamental importance throughout human history. Water from rivers is a basic natural resource, essential for various human activities. Therefore, riverbanks have attracted settlers from ancient times. Using rivers for irrigation, navigation and hydropower generation is of special significance — particularly to a country like India, where agriculture is the major source of livelihood of the majority of its population.
Question 3. Below are given names of a few lakes of India. Group them under two categories – natural and created by human beings. (a) Wular (b) Dal (c) Nainital (d) Bhimtal (e) Gobind Sagar (f) Loktak (g) Barapani (h) Chilika (i) Sambhar (j) Rana Pratap Sagar (k) Nizam Sagar (l) Pulicat (m) Nagarjuna Sagar (n) Hirakund
Answer:
Natural Lakes: Wular, Dal, Nainital, Bhimtal, Loktak, Chilika, Pulicat, Sambhar, Barapani,
Created by human beings: Gobind Sagar, Hirakud, Rana Pratap Sagar, Nagarjuna Sagar, Nizam Sagar
Question 4: Discuss the significant difference between the Himalayan and the Peninsular rivers.
Answer:
| Himalayan Rivers | Peninsular Rivers |
| Originate from the Himalayan ranges. | Originate from the Deccan Plateau |
| These are perennial rivers. | These are seasonal rivers. |
| They receive water from both rainfall and melting snow, ensuring a continuous flow. | These rivers are dependent on rainfall, leading to significant seasonal fluctuations in water levels. |
| They carry a lot of mud and sand because they start in the mountains. | They carry less mud and sand compared to Himalayan rivers. |
| They make big curves and create large areas of fertile land. | Not as curvy and have deltas where they meet the sea. |
Question 5: 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. |
| Start from various high areas like the Western Ghats and central highlands. | Mostly start from the Western Ghats. |
| They are generally longer and travel more distance across the plateau. | They are shorter because they quickly reach the Arabian Sea. |
| Create big deltas where they meet the sea, making flat, wide areas. | Form estuaries, which are narrower sea inlets, not wide deltas. |
| Carry a lesser amount of sediments, so form estuaries at their mouths. | Carry lesser amount of sediments, so form estuaries at their mouths. |
| They have a greater number of tributaries. | They have a lesser number of tributaries. |
Question 6: Why are rivers important for the country’s economy?
Answer: Rivers have been of fundamental importance throughout human history. Water from rivers is a basic natural resource, essential for various human activities. Some of them are:
- Water Supply: Rivers are a key source of water for domestic, agricultural, and industrial use.
- Irrigation: Many rivers provide the necessary water for irrigation, which is essential for growing crops.
- Energy Production: Rivers are used to generate hydroelectric power, a renewable energy source.
- Transportation: Rivers serve as natural highways for the transport of goods and people.
- Tourism: Many rivers have historical, cultural, or natural significance, attracting tourists.
- Fishing: Rivers support fisheries, which are a source of livelihood for many people.
- Environmental Benefits: Rivers help maintain natural landscapes, support biodiversity, and can even help in climate regulation.