1. Choose the right answer from the four alternatives given below:
(i) In which of the following states is the Wular lake located?
(d) Jammu and Kashmir
(ii) The river Narmada has its source at
(b) Amarkantak
(iii) Which one of the following lakes is a saltwater lake?
(a) Sambhar
(iv) Which one of the following is the longest river in Peninsular India?
(b) Godavari
(v) Which one amongst the following rivers flows through a rift valley?
(d) Tapi
2. Answer the following questions briefly:
(i) What is meant by a water divide? Give an example.
Ans: A water divide is an elevated area, such as a mountain or upland, that separates two drainage basins. An example is the water divide between the Indus and Ganga river systems
(ii) Which is the largest river basin in India?
Ans: The Ganga River Basin is the largest in India.
(iii) Where do the rivers Indus and Ganga have their origin?
Ans: Indus River: Near Manasarovar Lake, Tibet
Ganga River: From the Gangotri Glacier in Uttaranchal
(iv) Name the two headstreams of the Ganga. Where do they meet to form the Ganga?
Ans: The two headstreams are Alaknanda and Bhagirathi. They meet at Devprayag to form the Ganga.
(v) Why does the Brahmaputra in its Tibetan part have less silt, despite a longer course?
Ans: In Tibet, the Brahmaputra carries less water and silt due to cold and dry conditions. However, in India, it flows through regions with high rainfall, leading to a larger volume of water and more silt.
(vi) Which two Peninsular rivers flow through a trough?
Ans: The Narmada and Tapi rivers flow through a trough.
(vii) State some economic benefits of rivers and lakes.
Ans: Rivers provide water for irrigation, navigation, and hydropower generation. They have historically supported settlements, leading to the growth of major cities. Lakes also provide water for irrigation and support fisheries.
3. Group the lakes under natural and human-made categories:
Natural Lakes
Wular
Dal
Nainital
Bhimtal
Loktak
Chilika
Pulicat
Sambhar
Barapani
Human-made Lakes
Gobind Sagar
Rana Pratap Sagar
Nizam Sagar
Nagarjuna Sagar
Hirakud
4. Discuss the significant difference between the Himalayan and the Peninsular rivers:
Ans: Himalayan Rivers Perennial rivers (flow throughout the year)
Receive water from rainfall and snowfall.
Peninsular Rivers Seasonal rivers (dependent on rainfall)
Often dry up during the dry season.
5. Compare the east-flowing and the west-flowing rivers of the Peninsular plateau:
Ans: West-flowing Rivers There are only two long rivers: Narmada and Tapi
Flow into the Arabian Sea
Fewer tributaries
Form estuaries
Carry less sediment
East-flowing Rivers
Major rivers: Mahanadi, Cauvery, Godavari, Krishna, etc.
Flow into the Bay of Bengal
More tributaries
Form deltas
Carry more sediment than the west-flowing rivers.
6. Why are rivers important for the country’s economy?
Rivers are crucial for agriculture, which is a major livelihood in India.
They are essential for irrigation, navigation, and hydropower generation.
The fertile lands along riverbanks have supported ancient and modern settlements, many of which have become large cities contributing significantly to the economy.