NCERT Solutions for Chapter 3 Drainage System Class 11 Geography
Book Solutions1(i)
Which one of the following rivers was known as the ‘Sorrow of Bengal’?
(b) The Son
(c) The Kosi
(d) The Damodar
Answer
1(ii)
(a) The Indus
(b) The Brahmaputra
(c) The Ganga
(d) The Krishna
Answer
(c) The Ganga1(iii)
(a) The Ravi
(b) The Chenab
(c) The Indus
(d) The Jhelum
Answer
(c) The Indus1(iv)
(a) The Son
(b) The Narmada
(c) The Yamuna
(d) The Luni
Answer
(b) The Narmada1(v)
(a) Vishnu Prayag
(b) Rudra Prayag
(c) Karan Prayag
(d) Deva Prayag
Answer
(d) Deva Prayag2(i)
Answer
River Basin | Watershed |
The catchments of large rivers are called river basins. | The catchments of small rivulets and rills are often referred to as watersheds. |
These are larger in the area. | These are small in area. |
2(ii)
Answer
Dendritic drainage pattern | Trellis drainage pattern |
The drainage pattern resembling the branches of a tree is known as dendritic. | When the primary tributaries of rivers flow parallel to each other and secondary tributaries join them at right angles, the pattern is known as trellis. |
The drainage pattern of Northern plain is the example of such pattern. | The drainage pattern of Himalayan mountain is the example of such pattern. |
2(iii)
Answer
Radial drainage pattern | Centripetal drainage pattern |
When the rivers originate from a hill and flow in all directions, the drainage pattern is known as ‘radial’. | When the rivers discharge their waters from all directions in a lake or depression, the pattern is known as ‘centripetal’. |
The rivers originating from the Amarkantak range is the example of such pattern. | Sambhar Lake of Rajasthan is the example of such pattern. |
2(iv)
Answer
Delta | Estuary |
A Delta is a triangular landmass formed at the mouth of the river. | An Estuary is a funnel shaped formed at the mouth of the river. |
It is formed in the regions of low tides and coastal plains. | It is formed in the regions of high tides and rift valleys. |
These are extremely fertile and support agriculture. | They provide fishing ground and support inland transportation. |
The rivers like Ganga and Brahmaputra form deltas. | The rivers like Narmada and Tapi form estuaries. |
3(i)
What are the socio-economic advantages of inter-linking of rivers in India?
Answer
• The problems of floods and drought will get solved as excess water from an area can be transferred to water deficit areas.
• The inland waterway transportation will improve which will make the transportation of materials across the country easier.
• It will also help in imporving irrigational facilities which will increase the productivity.
• It will provide various opportunities such as hydro-electricity and fisheries activities.
3(ii)
Write three characteristics of the Peninsular river.
Answer
• These rivers originate in Peninsular plateau and central highland.
• These are seasonal and dependent on monsoon rainfall.
• These rivers are smaller having fixed course with well adjusted valleys.
4(i)
What are the important characteristic features of north Indian rivers? How are these different from Peninsular rivers?
Answer
• They originate in Himalayan mountain covered with glaciers.
• These rivers are perennial in nature because they receive water from glacier and rainfall.
• These rivers form deep gorges and V-shaped valleys in mountainous areas.
• It has long course, flowing through the rugged mountains experiencing headward erosion and river capturing.
• These rivers are young and youthful, active and deepening in the valleys.
These are different from peninsular rivers because of these reasons:
• The north Indian rivers have very large basins while peninsular rivers have relatively smaller basin.
• The north Indian rivers are perennial as they receive water from glaciers and rainfall while peninsular rivers receive their water only from monsoon rains.
• The north Indian rivers are antecedent and consequent leading to dendritic pattern in plains while peninsular rivers are super imposed, rejuvenated resulting in trellis, radial and rectangular patterns.
• The north Indian rivers are young and youthful, active and deepening in the valleys while peninsular rivers are old with graded profile, and have almost reached their base levels.
4(ii)
Suppose you are travelling from Haridwar to Siliguri along the foothills of the Himalayas. Name the important rivers you will come across. Describe the characteristics of any one of them.
Answer
The characteristics of Gandak:
• It rises in the Nepal Himalayas between the Dhaulagiri and Mount Everest and drains the central part of Nepal
• It comprises two streams, namely Kaligandak and Trishulganga.
• It enters the Ganga plain in Champaran district of Bihar and joins the Ganga at Sonpur near Patna.
• Its length is 630 Km.