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GEOGRAPHY
CLASS IX
CHAPTER 2
PHYSICAL FEATURES OF INDIA
(formative assessment-1)
Q.1. What is Plate Tectonics?
Ans. The concept of Plate Tectonics, developed in 1960s explains the origin of
continents, oceans and other landforms. Plate is a broad segment of lithosphere that floats
on asthenosphere continuously. The concept explains the movement of the crustal plate.
Q.2. What is the peninsular plateau composed of?
Ans. Igneous and metamorphic rocks.
Q.3. What are the longitudinal division of Himalayas?
Ans. a. Himadri b. Himachal c. Shiwaliks
Q.4. How are the Himalayas divided regionally or on the basis of river valleys?
Ans. a. Punjab Himalayas between river Indus and Satluj
b. Kumaon Himalayas between river Satluj and Kali
c. Nepal Himalayas between river Kali and Teesta
d. Assam Himalayas between river Teesta and Brahmaputra.
Q.5. What are distributaries?
Ans. Distributaries are the numerous channels which get split from the main river when it
is about to enter the sea.
Q.6. Identify the regional division of the Northern Plains.
Ans. a. Punjab Plains
b. Ganga Plain
c. Brahmaputra Plain
Q.7. What are the relief features that are found in the Northern Plains?
Ans. a. Bhabar b. Terai c. Bhangar d. Khadar
Q.8. Which landform feature was a part of Gondwanaland?
Ans. Peninsular plateau
Q.9. Which plateau lies between the Aravallies and the Vindhaya range?
Ans. Malwa plateau
Q.10. Where is the Aravali hills located?
Ans. The Aravali hills lie on the western and north-western margins of the peninsular
plateau in Rajasthan.
Q.11. Name the landmasses that were included in the Gondwanaland.
Ans. India, Australia, Southern Africa, South America
Q.12. What is a doab?
Ans. The land between two rivers is known as a doab. ‘Do’ means two and ‘ab’ means
water.
Q.13. What are riverine islands?
Ans. In the lower course of the river, due to gentle slope, the velocity of the river
decreases and it involves into depositional work leading to the formation of riverine
islands. Ex. Majuli in Brahmaputra
Q.14. Which island in Lakshadweep has got a bird sanctuary?
Ans. Pitli island
Q.15. Differentiate between Convergent and Divergent Plate Boundaries.
Ans.
CONVERGENT PLATE BOUNDARIES
DIVERGENT PLATE BOUNDARIES
1. The tectonic plates move closer to
1. Tectonic plates move away from eacheach-other in convergent plate
other in divergent plate boundaries
boundaries.
2. The two plates coming together may
2. The two plates drift away from eachother creating gap between the two.
3. Convergence of plates may result into
3. Divergence of plates may result into
volcanic eruption.
4. Formation of Himalayas is a result of
4. Formation of Great Atlantic drift is a
result of divergence of plates.
either collide, or may slide under the
other.
activities like earthquake.
convergence of plates.
Q.16. How was the Himalayas formed?
Ans. a. Himalayas are the product of a process of the convergence of Indo-Australian
plate and
Eurasian plate.
b. Some 70 million years ago, the Indian plate started moving towards the Eurasian plate
and the
Tethys Sea between the two began to contract due to this movement.
c. There occurred the lateral compression of the marine sediments in the bed of the
Tethys Sea.
d. Geologists believe that the sediments got folded giving rise to the ranges of Himalayas.
Q.17. What is the shape and size of the Himalayas?
Ans. a. Himalayas run in a west –east direction from Indus to Brahmaputra covering
2400km.
b. They form an arc.
c. Width of the Himalayas varies from 400km in Kashmir to 150 km in Arunachal
Pradesh.
d. Average height of the Himalayas also varies from about 6000m to 900m above the sea
level.
Q.18. “Himalayas are the young fold mountains.” Justify the given statement.
Ans. A. Himalayas were formed as result of convergence of plates that further resulted
into thefolding of sediments from the Tethys Sea. Therefore, they are Fold Mountains.
b. Himalayas have conical peaks and deep valleys which indicate that Himalayas are still
young.
c. Geologists believe that the Height of the Himalayas is still rising.
d. Himalayas are 7 million years old. This time period is considered as very young in the
geological time scale.
Therefore, we can say that the Himalayas are “Young Fold Mountains.”
Q.19. Write the characteristics of the following:
Ans. I. HIMADRI
It is the northernmost range of Himalayas.
Also known as “Great Himalayas” or “Inner Himalayas”.
It is the most continuous range consisting of very high peaks.
Average height of Himadri range is 6000m
Core of the Himadri range is composed of granite.
It is covered with snow almost throughout the year and a number of glaciers descend
from it.
II. HIMACHAL
This range lies to the south of Himadri and forms the most rugged mountain system.
Also known as “Lesser Himalayas”.
It is mainly composed of highly compressed and altered rocks.
Altitude varies between 3700 to 4500m and average width is 50m.
Further divided into – Pir Panjal range, Mahabharata and Dhauladhar range.
Well known for hill stations- Kashmir valley, Kullu valley, Kangra valley.
III. SHIWALIKS
It is the outermost range of Himalayas.
Width extends over 10-50km and altitude 900-1100m.
Composed of unconsolidated sediments brought down by rivers.
Covered with thick gravel and alluvium.
Longitudinal valleys between Himachal and Shiwaliks are found known as ‘Duns’.
Ex.- Dehradun, Patlidun, Kotlidun.
IV. PURVANCHALS
Beyond the Dihang gorge, Himalayas bend sharply to the south and spread along the
eastern boundary of India known as Purvanchals or Eastern hills.
They are mostly composed of strong sandstones which are sedimentary rocks.
Forms a natural frontier between India and Myanmar.
Covered with dense forest and mostly run as parallel range.
It is comprised of Patkai hills, Naga hills, Manipur hills, and Mizo hills.
Q.20. How was the Northern Plains formed?
Ans. 1. After the formation of the Himalayas out of the Tethys sea, the vast basin was
formed at
the foothills of the Himalayas.
2. Thereafter, the deposition of alluvium in the vast basin was done for the millions of
years.
3. This deposition was done mainly by the three river systems – Indus, Ganga, and
Brahmaputra that resulted into the formation of Northern Plains.
Q.21. Why the Northern Plains are most densely populated areas of the world?
Ans. A. FLAT TERRAIN
The Northern Plain region has got flat topography almost without any undulations
making it easier for the human beings to construct houses, industries, transport and to do
agriculture.
B. ADEQUATE CLIMATE
The Northern Plains experience almost every type of climate giving a wide variety of
doing agriculture.
C. FERTILE SOIL
The soil present here is highly fertile because of the sedimentation done by the rivers
making it suitable for agriculture.
D. RIVER SUPPLY
Many rivers and tributaries are present here providing regular supply of water for
agriculture, industries and other domestic works.
Therefore, Northern Plains are densely populated regions of the world.
Q.22. Differentiate between the following:
Ans. A. Bhabar and Terai
BHABAR
TERAI
1. It lies to the south of Shiwalik range.
1. The belt exist to the south of Bhabar
area.
2. The width ranges between 8 to 16km.
3. The area is highly coarse in nature due
to many pebbles and ‘kankars’ found
over here.
2. It is almost parallel to the Bhabar.
3. The area has got highly fine sediments
due
to the deposition made by several streams.
4. Main feature is that river disappear in
the Bhabar region because if big pores
present in it.
4. Since the river re-emerges back in this
region, the area becomes highly swampy
and marshy.
5. Vegetation found here is very less.
5. Very dense vegetation is found in Terai
region.
B. Khadar and Bhangar
KHADAR
BHANGAR
1. Khadar is the new alluvium that is
1. Bhangar is the old alluvium that is
formed after the change in the course of the
river.
2. Being new, khaddar is more fertile.
2. Since bhangar has been used up,
therefore, the fertility is comparatively less.
3. Soil is very fine in nature.
3. The texture of the soil is coarse because
of concentration of kankars.
4. The soil is comparatively darker in
colour.
5. It is slightly above from the flood plains.
formed after the recent deposition made by
the river.
4. The colour of the soil is lighter.
5. It lies near to the flood plains.
C. Western Ghats and Eastern Ghats
WESTERN GHATS
EASTERN GHATS
1. Western Ghats mark the western
boundary of the peninsular plateau,
stretching from Gujarat to Kerela.
1. Eastern Ghats mark the eastern boundary
of the peninsular plateau, stretching from
Orissa to Kerela.
2. It is a regular stretch of highland.
2. They are dissected and irregular because
of the major rivers flowing through them.
3. Western ghats are comparatively more
3. Height of eastern ghats is comparatively
less than western ghats ranging from 600900m.
4. Western ghats receive more rainfall due
4. Rainfall received is comparatively less
because the monsoon winds move parallel
to the eastern ghats.
in height i.e. from 900-1600m.
to orographic rainfall.
5. Highest peak of western ghats is Anai
Mudi, followed by Doda Betta.
5. Highest peak of eastern ghats is
Mahendragiri.
D. Western Coastal Plains and Eastern Coastal Plains
WESTERN COASTAL PLAINS
EASTERN COASTAL PLAINS
1. Western Coastal Plains is a belt of plain
1. Eastern Coastal Plains is a belt of plain
region lying towards the east between
eastern ghats and Bay of Bengal.
2. This belt of plains is narrow in width.
2. Eastern Coastal Plains are comparatively
wider.
3. Western coastal plains are less fertile
3. Eastern coastal plains are very fertile
because rivers like Mahanadi, Godavari,
Krishna, Kaveri deposit their sediments
during delta formation.
4. Western plains receive more rainfall.
4. Eastern plains receive comparatively
lesser
rainfall.
5. From North to South, Western Coastal
5. From North to South, Eastern Coastal
plains are divided into Northern Circars
and Coromandal Coast.
region lying towards west between
western ghats and Arabian sea.
because no major river is engaged in
sediment deposition.
plains are divided into Konkan Coast,
Kannad Coast and Malabar Coast
E. Andaman and Nicobar Islands and Lakshadweep Islands
ANDAMAN AND NICOBAR ISLANDS
LAKSHADWEEP ISLANDS
1. These island groups are located in Bay
1. These islands are located in Arabian Sea.
of Bengal.
2. They are volcanic in origin.
2. They are formed because of coral
deposition.
3. Andaman and Nicobar is a chain of
3. Lakshadweep is a cluster of islands.
4. These island groups are far away from
the mainland.
4. This island group is closer to the
mainland.
5. Administrative unit is Port Blair.
5. Administrative unit is Port Blair.
islands.
Q.23. Give the characteristics features of the Indian desert.
Ans. a. Indian desert is an undulating sandy plain covered with sand dunes.
b. The region receives very low rainfall below 150mm per year.
c. The region has arid climate with low vegetation cover.
d. Barchans (crescent shaped dunes) and sand dunes cover large area of the desert.
e. Luni is the only major seasonal river in this region.
Q.24. How can you say that the diverse physical features of India makes the country
richer in its natural resources?
Ans. a. The northern mountains are the major source of water and forest wealth.
b. The northern plains provide us with number of agricultural crops.
c. The plateau is the store house of the minerals which is highly important for the
industrialization of the country.
d. The coastal region and island groups provide sites for fishing and port activities.
Thus, we can say that the diverse physical features of India make the country richer in its
natural resources.