CBSE Class 7 Geography Revision Worksheet Set A

Atmosphere and Temperature

Give answer to the following questions approximately in 1- 15 words

Q1. What do you understand by the Atmosphere?
Ans. The earth is surrounded by a cover of air. This cover is known as Atmosphere.

Q2. Why we study Atmosphere in Geography?
Ans. Because Atmosphere is responsible for creating and maintaining of plants and animal life on the Earth.

Q3. Name the layers of Atmosphere.
Ans. 1.Troposphere 2. Stratosphere
3. Mesosphere 4. Thermosphere (Ionosphere+ Exosphere)

Q4. Which is called Tropopause limit?
Ans. Tropopause limit is the boundary between Troposphere and Stratosphere.

Q5. What do you understand by Exosphere?
Ans. The outermost layer of Atmosphere is called Exosphere. It has gases like Hydrogen and Helium.

Q6. What are the elements other than the gases present in the Atmosphere?
Ans. Water vapours and dust particles.

Q7. What is air pollution?
Ans. Foreign substances in the Atmosphere make air unhealthy. This is called air pollution. Smoke, dust particles and pesticides are the main sources of air pollution.

Q8. What is temperature and what are the units of measuring the temperature?
Ans. The heat of the air and the internal heat of a good or living being, is called temperature. It is measured in Celsius and Fahrenheit.

Q9. Why is the temperature very high on the Equator?
Ans. The rays of the sun fall directly on the Equator. Therefore the temperature is high over there.

Q10. Why there is difference in day time and night time temperature?
Ans. The Earth gets heat from the Sun during day and releases it during the night. That's why there is a high temperature during days and low at nights.

Q11. Why temperature of Shimla is lower than that of Chandigarh?
Ans. Shimla is situated higher above the sea level than that of Chandigarh. When we go higher above the sea level, the temperature starts falling. That's why Shimla is colder than Chandigarh.

Give answers to the following questions in about 50- 60 words

Q12. What are the main factors that cause air pollution?
Ans.
Solid pollutants: -
1. Volcanoes pollute the air by dust particles.
2. Smoke from the burning of fuels release carbon particles into the air.
Gaseous pollutants:-
1. Exhaust materials of automobiles pollute the air.
2. Smog causes air pollution.

Q13. What we call the lower layer of the atmosphere?
Ans. 1. The lowest layer of the atmosphere is called Troposphere. Its average height is 12 Km.
2. The entire weather phenomenon like rainfall, storm, clouds etc. takes place only in this layer.
3. The 75% of all the air, is present in this layer.

Q14. Write the ratio of main gases in the air.
Ans. 1.Nitrogen- 78.03%, 2. Oxygen- 20.99%
3. Argon- 0.94% 4. Carbon dioxide- 0.03%
5. Hydrogen- 0.01% 6. Dust particles and water vapours.

Q15. In which layer of the Atmosphere the Ozone gas exists? Why is it so important?
Ans. Ozone gas exists in Stratosphere layer.it absorbs the Ultraviolet rays of the Sun, which are very harmful to the life of living beings on the earth.

Fill in the blanks

1. As we go up to the hills the temperature decreases.
2. The main sources of the temperature are Sun and internal part of the Earth.
3. The Ozone gas absorbs Ultraviolet rays.
4. The electrically charged particles are found in Thermosphere or Ionosphere layer.
5. The wireless communication system works under Radio waves.
6. Nitrogen gas is found in maximum quantity in atmosphere.

More Question

Q 1. Fill in the blanks. (1X10)

1. The place where the river originates is called ________________.

2. Water vapor is confined only to the ______________ layer of the atmosphere.

3. ___________ is the coldest layer in the atmosphere.

4. The steep sloping segment f the swift flowing river is called a ________________.

5. The fine duct particles deposited extensively is known as _______________.

6. The lower part of the thermosphere is called ___________________.

7. The highest waterfall in the world is _____________. It is located in ______________.

8. Weathering evolves ________ and ________________ of rocks.

Q2. Answer the following question. (2X5)

1. Write the names of different layers of atmosphere. Draw a well labeled diagram of it.

2. Why is wind the most important agent of erosion in the desert?

3. Why does the density of air decrease with increase in height?

4. Differentiate between meanders and moraines.

5. How is ox-bow lake form?

Please refer to attached file for CBSE Class 7 Geography Worksheets (15) - Revision Worksheet