PHYSICAL GEOGRAPHY (UNIT - 1)

 

Class 10 geography

UNIT - 1

PHYSICAL GEOGRAPHY 

1. What is landform?
Ans: The surface of the Earth is being characterised by varied types of features. These features present over the earth's surface are called landforms.


2. What is geomorphology?
Ans: Geomorphology is a particular branch of Geography with studies about the origin, evolution, morphology and distribution of landforms.



3. Give some examples of exogenic processes of Earth's surface.
Ans: Wind,  rainfall,  rivers , glaciers , Ocean waves and currents are some examples of exogenic factors.



4. Give some examples of endogenic factors of Earth's surface.
Ans: earthquake and volcanoes are some examples of endogenic factors of Earth's surface.



5. What is called geomorphic processes?
Ans: The exogenic and endogenic processes which involved in the creation of landforms are collectively called geomorphic processes. Winds and glaciers are the two most important geomorphic processes.



6. What are the main activities of wind?
Ans: The main activities of wind are -
a) Erosion
b) transportation and
c) deposition.


7. What is deflection?
Ans: In desert area , the sand and small rock particles are easily carried away by wind due to thin vegetative cover and sandy surface. In this way, some areas of the desert are relatively lowered by wind actions, and this process is called as deflation.


8. What are oasis?
Ans: As a result of transportation of materials to other parts , some areas may be lowered down almost to the level of underground water giving rise to some depressions. These are termed as oasis.


9. What is sand dune?
Ans: The deposits of sand may take the form of hills in due course of time. Such hill - like sand deposits are known as sand dunes.


10. What is longitudinal sand dunes?
Ans: Some sand dunes are formed longitudinally along the direction of wind. These are called longitudinal sand dunes.


11. What are transverse sand dunes?
Ans: Some sand dunes are formed transverse to the wind direction. Such sand dunes are called transverse sand dunes.


12. What are barkhans ?
Ans: In certain desert areas , some sand dunes become cresent - shaped. These are called barkhans.


13. What are the factors depended on the shape and size of sand dunes?
Ans: The factors which depended on the shape and size are -
a) properties of wind
b) wind direction and energy
c) vegetative cover
d) surface structure etc .


14. Mention a feature of desert landscape.
Ans: Sand dunes.



15. Draw a picture of barkhan.

16. What is abrasion?
Ans: The wind blown sands at high velocity hit the elevated lands on their way and thereby erode them. Such erosion is called abrasion. Abrasion process is responsible for creation of inselberg , yardang and other kinds of erosional features.


17. What is inselberg?
Ans: The inselberg is an isolated low hillock .

The upper part of inselberg is steep due to high intensity of wind atcion than on its lower part.



18. What is yardang?
Ans: Yardang is a feature of desert areas, which is usually patterned by elongated ridges and shallow grooves .

19. What is attrition?
Ans: Attrition is a process of wind erosion in desert. The process by which the sand and rock particles are broken into smaller pieces through their mutual collision is known as attrition.



20. What is the average annual rainfall in the desert ?
Ans: Less than 20 cm.



21. What is sheet flood?
Ans: The flood that occurs covering large areas of desert is known as sheet flood.



22. What is glacier?
Ans: The slow moving snow and ice blocks when come down the slope are called glacier.



23. Presently, how many percent of Earth's land area is under the impact of glacial actions?
Ans: 1 percent.



24. What are the three works of glaciar?
Ans: The three works of glaciar are as follows:
a) erosion
b) transportation
c) deposition



25. Write about the types of glaciar.
Ans: The glaciars can be divided into three types based on the situation and environment of the snow - covered regions. These are :

a) Continental glacier: These glaciers cover extensive areas of the polar regions. Northern Canada, Greenland, Scandinavia , Antarctic etc. are extensively covered by the continental glaciers. These glaciers move downslope very slowly according to the surface gradient.

b) Mountain or Alpine or Valley glacier: These glaciers originate in the high altitude regions of the mountains. They are found mostly in the Alps of Europe, the Rockies of North America and the Himalayas of Asia . Generally they flow through the valleys confined between two mountain ranges. They are comparatively little faster than the continental glaciers.

c) Piedmont glacier : These glaciers originate in the Piedmont zone of the mountains. So , they are called Piedmont glaciers. Such Piedmont glaciers are common in Alaska of North America.


26. Give an example of horn.
Ans: Metahorn in the Swiss Alps.



27. What is hanging valley?
Ans: Hanging valley is a erosional feature created by glaciars. The tributary glaciers while meeting the main glaciers appear to be hanging over the main glaciers. So the valley of the tributary glacier is called hanging valley.



28. What are moraines?
Ans: Glaciers carry different types of materials in addition to ice blocks while flowing through air valleys. All such materials or sediments are collectively known as moraines .

The different types of moraines are :
a) Lateral Moraines
b) End or Terminal Moraines
c) Medial Moraines