NCERT Solutions for Class 9 Social Science Chapter 8 - The Drainage System

Answer:

(d) Jammu and Kashmir

Answer:

(c) Amarkantak

Answer:

(a) Sambhar

Answer:

(c) Godavari

Answer:

(d) Tapi

Answer:

A raised area separating the head streams of two different river systems is called a water-shed or water-divide. In India, the Ganga river system flows eastward and drains into the Bay of Bengal, while the Indus river system flows westward and drains into the Arabian Sea. The area near Ambala with a height of 283 metres is the water divide between the Ganga and the Indus. It separates two drainage basins.

Answer:

The Ganga-Brahmaputra river basin is the largest in India. The Ganga river is 2,525 km. long and the Brahmaputra river is 2,900 km. long. The two rivers join together to form the largest delta of the world.

Answer:

River Indus and Ganga are Himalayan rivers.
(a) River Indus rises in Tibet near Lake Mansarovar.
(b) River Ganga rises from the Gangotari Glacier.

Answer:

The head waters of the Ganga called the Bhagirathi is fed by the Gangotari Glacier and is joined by the Alaknanda at Devaprayag in Uttarakhand. The two join to form the Ganga river.

Answer:

Most of the course of the Brahmaputra lies in Tibet. It enters India in Arunachal Pradesh. The river is called Tsangpo in Tibet. Here, the volume of water of the river is less and has less silt. But in India, the river has large volume of water and more silt. The river has a braided channel in Assam.

Answer:

Narmada and Tapi.

Answer:

Economically, rivers are very beneficial for a nation’s economy. Rivers provide us valuable resources such as alluvial soils, water for irrigation facilities, water transports in coastal regions, etc. Recreation, tourist promotion and fishing are also being developed along water fronts to gain economic benefits.

Answer:

Natural lakes: (a) Wular, (b) Dal, (c) Nainital, (d) Bhimtal, (f) Loktak, (g) Barapani, (h) Chilika, (i) Sambhar, (l) Pulicat.
Man-made lakes: (e) Gobind Sagar, (j) Rana Partap Sagar, (k) Nizam Sagar, (m) Nagarjuna Sagar, (n) Hirakud.

Answer:

Answer:

Answer:

Role of Rivers in the Economy
(a) Cultural Importance: Rivers have been of fundamental importance throughout human history. The areas along the banks of rivers have witnessed great cultural and economic progress since ancient times. Rivers are an integral part of our folklore and folk songs.
(b) A Natural Resource: Water from the rivers is a basic natural resource, essential for human, agricultural and industrial activities.
(c) Agricultural Areas: Rivers and their associated alluvial soils provide the most productive agricultural lands of the country. The Ganga, the Kaveri and other deltas have traditionally been the rice growing areas. An agriculture dependent on the variability of the monsoons, irrigation from rivershas been the backbone of the development of Indian agriculture.
(d) Settlements: The valleys contain dense and concentrated settlements. Most of the large cities are located on rivers. Not only do rivers provide us with essential water supplies, but they also receive, dilute and wash away wastes from settlements.
(e) Industrial Development: Industrial development has flourished along the rivers as many industrial processes rely on water – as a raw material, as a coolant and for the generation of hydroelectricity.
(f) Transportation: Rivers provide primary channels of inland transportation, not only directly in the form of navigable waterways, but also indirectly through their valleys, where roads, railway lines and other routes are built.
(g) Tourism: Recreation, tourist promotion and fishing are also being developed along water ways.

Answer:

The Ganga-Brahmaputra River basin is the largest river basin in India.

Answer:

Kunchikal fall is the biggest waterfall in India.