CBSE Class 9 Social Science Physical Features of India Assignment Set A

Physical Features of India

Choose the right answer from the four alternatives given below.

Question : A landmass bounded by the sea on three sides is referred to as
(a) Coast
(b) Island
(c) Peninsula
(d) None of the above
Answer : (c)

Question : Mountain ranges in the eastern part of India forming its boundary with Myanmar are collectively called
(a) Himachal
(b) Uttarakhand
(c) Purvachal
(d) None of the above
Answer : (c)

Question : The western coastal strip, south of Goa is referred to as
(a) Coromandel
(b) Konkan
(c) Kannad
(d) Northern Circar
Answer : (c)

Question : The highest peak in the Eastern Ghats is
(a) Anai Mudi
(b) Kanchenjunga
(c) Mahendragiri
(d) Khasi
Answer : (c)

Answer the following questions briefly.

Question : What is the bhabar?
Answer : The northern plains are generally described as flatlands, with no variations in its relief. But,It is not true. These vast plains also have diverse relief features. According to the variations in relief features, the Northern plains can be divided into four regions. The rivers, after descending from the mountains deposit pebbles in a narrow belt of about 8 to 16 km in width lying parallel to the slopes of the Shiwaliks. This region is known as bhabar.

Question : Name the three major divisions of the Himalayas from north to south.
Answer :
1. The northernmost range is known as The Great or Inner Himalayas or Himadri
2. Himachal or Lesser Himalaya
3. Outer Himalayas or Shiwaliks

Question : Which plateau lies between the Aravali and the Vindhya ranges?
Answer : The Malwa plateau lies between Aravali and Vindhya ranges.

Question : Name the island group of India having a coral origin.
Answer : Lakshadweep Islands is the island group of India having a coral origin.

Distinguish between

Question : Bhangar and Khadar
Answer :
Bhangar
1. Lies above flood plains of the river.
2. Older alluvium or old soil and forms the largest part of the Northern Plains
Khadar
1. It is a newer, younger deposit of flood plains. Renewed every year.

Question : the Western Ghats and the Eastern Ghats
Answer :
The Western Ghats
1. Lies parallel to the Western Coast.
2. They are continuous and can be crossed through passes only
3. The Western Ghats’ average elevation is 900 – 1600 metres
4. The Western Ghats cause orographic rain by facing the rain-bearing moist winds to rise along the western slopes of the Ghats.
5. The height of the Western Ghats progressively increases from north to south.
The Eastern Ghats
1. Lies parallel to the Eastern Coast.
2. They are discontinuous and irregular and
3. The Eastern Ghats are dissected by rivers flowing into the Bay of Bengal.
4. The Eastern Ghats average elevation is 600 metres 

Question : Which are the major physiographic divisions of India?
Answer :
The major physiographic divisions of India are
1. The Himalayan Mountains
2. The Northern Plains
3. The Peninsular Plateau
4. The Indian Desert
5. The Coastal Plains
6. The Islands

Write short notes on the following..

Question : The Central Highlands
Answer : Central Highlands and the Deccan Plateau. The part of the Peninsular plateau lying to the north of the Narmada river, covering a major area of the Malwa plateau, is known as the Central Highlands. The Central Highlands are wider in the west but narrower in the east. The eastward extensions of this plateau are locally known as the Bundelkhand and Baghelkhand. The Chotanagpur plateau marks the further eastward extension, drained by the Damodar river.

Question : The Island groups of India
Answer : Lakshadweep Islands
Lakshadweep group of islands is composed of small coral islands. Earlier they were known as Laccadive, Minicoy and Amindive. In 1973, these were re-named as Lakshadweep. It covers a small area of 32 sq km. Kavaratti Island is the administrative headquarters of Lakshadweep. This island group has a great diversity of flora and fauna. The Pitti island, which is uninhabited, has a bird sanctuary.

Answer the following questions briefly.

Question : What are tectonic plates?
Answer : The convectional currents present below the solid layer of Earth's crust split the crust or the lithosphere into a number of large fragments. These fragments are called tectonic or lithospheric plates.

Question :  Which continents of today were part of the Gondwana land?
Answer : The continents that were part of Gondwana land are Australia, Antarctica and South America

Question :  What is the bhabar?
Answer : The bhabhar is that part of the Northern Plains where the rivers, after descending from the mountains, deposit pebbles. It is a narrow belt, having a width of about 8 to 16 km and lying parallel to the slopes of the Shiwaliks

Question :  Name the three major divisions of the Himalayas from north to south.
Answer : The three major divisions of the Himalayas from north to south are the Great Himalayas/Inner Himalayas/Himadri (Northernmost division), the Lesser Himalayas/Himachal and the Shiwaliks (Southernmost division).

Question :  Which plateau lies between the Aravali and the Vindhyan ranges?
Answer : Malwa plateau lies between the Aravali and the Vindhyan ranges.

Question : Name the island group of India having coral origin.
Answer : Lakshadweep Islands are composed of small coral islands.

Distinguish between

Question :  Converging and diverging tectonic plates
Answer : (i)The Earth's crust is broken up into several lithospheric or tectonic plates. These plates are constantly moving atop the Earth's mantle (semi-solid layer of molten rocks). Based upon their motion, tectonic plates are referred to as converging or diverging. Converging tectonic plates move towards each other and form convergent boundary. Diverging tectonic plates move away from each other and form divergent boundary.

Question :  BhangarandKhadar
Answer : (ii)Bhangaris the terrace-like feature present above the flood plains of the rivers. It is composed of older alluvium. It is the largest part of the Northern Plain. The soil of this region contains calcerous deposits locally known as kankar.
The newer, younger deposits of the flood plains are called khadar. This region is very fertile as it gets renewed almost every year. Hence, it is ideal for intensive agriculture.

(iii) Western Ghats and Eastern Ghats

Question : Describe how the Himalayas were formed.
Answer : According to the Theory of Plate Tectonics, the Earth's crust was initially a single, giant supercontinent called Pangea. Its northern part was the Angara land and the southern part was the Gondwana land. The movement of the molten material below the Earth's crust caused the crust or the lithosphere to break up into a number of large fragments called lithospheric or tectonic plates. Another important feature of the Earth's crust at the time was the geosyncline—a narrow, shallow, elongated basin with a sinking bottom in which a considerable thickness of sediments were deposited by the rivers coming from Angara land and Gondwanaland—called the Tethys. After separating from the Gondwana land, the Indo-Australian Plate drifted towards the north in the direction of the Eurasian Plate. This resulted in the collision of the two plates, and due to this collision, the sedimentary rocks in the Tethys got folded to form the mountain system of western Asia and the Himalayas.

Question : Which are the major physiographic divisions of India? Contrast the relief of the Himalayan region with that of the Peninsular plateau.
Answer : The major physiographic divisions of India are:
(i) The Himalayan Mountains
(ii) The Northern Plains
(iii) The Peninsular Plateau
(iv) The Indian Desert
(v) The Coastal Plains
(vi) The Islands

Question : Give an account of the Northern Plains of India.
Answer : The Himalayan upliftment out of the Tethys Sea andthe subsidence of the northern flank of the Peninsular Plateau resulted in the formation of a large basin. Gradually, the rivers flowing from the mountains in the north and the peninsular plateau in the south filled up this depression with deposits of sediments. This led to the formation of the Northern Plains of India.
The formation of the Northern Plains owes largely to the interplay of three major river systems, namely - the Indus, the Ganga and the Brahmaputra along with their tributaries. This physiographic division spreads over an area of 7 lakh square kilometres, and is 2,400 kilometres long and 320 kilometres broad. It is a densely populated region. The rich soil cover, adequate water supply and favourable climate make the region agriculturally very productive.
The Northern Plains are broadly divided into three sections.
The Punjab Plains -Western part of the Northern Plains; formed by the Indus and its tributaries
The Ganga Plains - Largest part of the Northern Plains; extends between Ghaggar and Teesta rivers
The Brahmaputra Plains - Eastern part of the Northern Plains; formed by the Brahmaputra and its tributaries
According to the variations in relief features, the Northern Plains are divided into four regions.
Bhabar- Narrow belt of pebbles lying parallel to the slopes of Shiwaliks
Terai- Wet, swampy, marshy region south of the bhabarbelt
Bhangar- Terrace-like feature composed of older alluvium, lying above the flood plains
Khadar- Newer, younger deposits of the flood plains

Question : Write short notes on the following.
Answer : (i) The Indian Desert
Lying towards the west of the Aravali Hills, the Indian Desert is an undulating sandy plain covered with crescent-shaped and longitudinal sand dunes. This region is characterised by very little rainfall, an arid climate and low vegetation cover. Streams appear only during the rainy season. Luni is the only large river in this region.
(ii) The Central Highlands
The part of the Peninsular Plateau lying to the north of the Narmada River, covering a major area of the Malwa Plateau, is known as the Central Highlands. They are bound by the Vindhya Range from the south and by the Aravali Hills from the northwest. The further westward extension merges with the Indian Desert while the eastward extension is marked by the Chotanagpur Plateau. The rivers draining this region flow from southwest to northeast. The Central Highlands are wider in the west but narrower in the east.

(iii) The Island groups of India
India has two groups of islands. The Lakshadweep Islands lie in the Arabian Sea, to the southwest of the mainland. The Andaman and Nicobar Islands lie in the Bay of Bengal, to the southeast of the mainland. Lakshadweep is composed of small coral islands, covering a small area of 32 square kilometres. Kavaratti Island is its administrative headquarters. The Andaman and Nicobar Islands are bigger in size and are more numerous and scattered. The entire group of islands is divided into Andaman (in the north) and Nicobar (in the south).
Both these island groups are rich in flora and fauna, and are of great strategic importance to the country.