Oxford University Press solutions for Voyage Geography [English] Class 7 chapter 3 - Composition and Structure of the Atmosphere [Latest edition]

Discuss the importance of the different layers of the atmosphere?

What would happen to the earth if the atmosphere disappeared?

We often leave the lights switched on and fans running when we are not in the room. We switch on the air-conditioning even though we don’t really need it. We insist on being dropped to school in the car every day. Thus, we waste valuable energy which is generally produced by burning coal and petroleum. As you know, the burning of these fuels release gases that pollute the atmosphere.
Make a list of the similar things that we do without realizing that we are destroying the environment. Think of the ways that we can behave differently.

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______ per cent of the atmosphere is made of nitrogen.

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Along with carbon dioxide and methane, ___________ is a potent greenhouse gas.

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The rate at which the temperature drops in the ____________ is 1°C per 165 metres.

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The _________________ is the layer of the atmosphere that help in radio transmission.

The upper part of the thermosphere is called the ______.

Match the following.

Choose the correct answer.
This per cent of the atmosphere is composed of nitrogen.

Choose the correct answer.
21 per cent of the atmosphere is composed of

Choose the correct answer.
This gas protects us from the harmful ultraviolet radiation.

Choose the correct answer.
The rate at which the temperature drops in the troposphere is called

Choose the correct answer.
This layer of the atmosphere has the lowest temperature.

State whether the following is true or false.
The earth’s atmosphere contains 99 per cent oxygen, which is essential for life.

State whether the following is true or false.
The stratosphere is the lowest layer of the atmosphere.

State whether the following is true or false.
The temperature drops at the rate of 1°C per 185 metres in the atmosphere.

State whether the following is true or false.
The stratosphere extends from the top of the troposphere up to 80 km above the surface of the earth.

State whether the following is true or false.
Communication satellites orbit in thermosphere

How is the atmosphere kept in place around the earth?

Name the important gases that are found in the atmosphere.

How is carbon dioxide a useful gas for life on earth?

What is the troposphere?

What is the difference between the troposphere and the tropopause?

Write briefly about the layers of the atmosphere

State any three characteristics of the stratosphere

What is ozone? What is the ozone layer? How is the presence of ozone layer essential to preserve life on earth?

State any three characteristics of the mesosphere.

Why is the thermosphere important?

Explain the significance of the earth’s atmosphere.

This is a picture of a supersonic aircraft.

In which layer of the atmosphere does this airplane normally fly?

This is a picture of a supersonic aircraft.

This layer of the atmosphere is also known to protect living beings from the harmful rays of the sun. How?

In your notebooks, draw a diagram showing the layers of the atmosphere. Mark clearly the ozone layer, the height at which a jet plane can fly and also the height up to which birds can fly.