Haryana State Board HBSE 7th Class Social Science Solutions Geography Chapter 4 Air Textbook Exercise Questions and Answers.
Haryana Board 7th Class Social Science Solutions Geography Chapter 4 Air
HBSE 7th Class Geography Air Textbook Questions and Answers
Air Class 7 HBSE Geography Question 1.
Answer the following questions:
(i) What is atmosphere?
A huge blanket of air that surrounds the earth is called atmosphere.
(ii) Which two gases make the bulk of the atmosphere?
Two gases that make the bulk of the atmosphere are nitrogen and oxygen.
(iii) Which gas creates greenhouse effect in the atmosphere?
Carbon dioxide gas.creates greenhouse effect in the atmosphere.
(iv) What is weather?
Weather is the sum total of atmospheric conditions of si specific place, at a specific time regarding temperature, humidity, air pressure, clouds, winds etc.
(v) Name three types of rainfall.
Three types of rainfall are:
(a) Convectional rainfall
(b) Orographic rainfall
(c) Cyclonic or Frontal rainfall.
(vi) What is air pressure?
Air has weight and exerts pressure. Hence, air pressure is an impact which occurs due to air weight.
Air Question Answer HBSE 7th Class Geography Question 2.
Tick the correct answer:
(i) Which of the following gases protects us from harmful sun rays?
(a) Carbon dioxide
(ii) The most important layer of the atmosphere is :
(iii) Which of the following layers of the atmosphere is free from clouds?
(iv) As we go up the layers of the atmosphere, the pressure ________.
(c) remains the same
(v) When precipitation comes down to the earth in the liquid form, it is called ________.
Air Class 7 Notes HBSE Geography Question 3.
Match the following :
|(i) Trade winds||(a) Incoming solar energy|
|(ii) Loo||(b) Seasonal wind|
|(iii) Monsoon||(c) Hotizontal movement of Air|
|(iv) Wind||(d) Layer of ozone gas|
|(e) Permanent wind|
|(f) Local wind|
|(i) Trade winds||(e) Permanent wind|
|(ii) Loo||(f) Local wind|
|(iii) Monsoon||(b) Seasonal wind|
|(iv) Wind||(c) Hotizontal movement of Air|
Air Class 7 Questions HBSE Geography Question 4.
(i) Wet clothes take longer time to dry on a humid day.
On a humid day, evaporation from wet clothes takes place slowly in the atmosphere due to low temperature. Hence wet clothes take longer time to dry on a humid day.
(ii) Amount of insolation decreases from equator towards poles.
Insolation comes through vertical rays on equator. As we go iip from equator towards poles, the sun rays become slanting. The slanting rays take up more space, the degree of hotness is felt less. Hence the amount of insolation decreases from equator towards poles.
HBSE 7th Class Geography Air Important Questions and Answers
Very Short Answer Type Questions
Air Class 7 Questions And Answers HBSE Question 1.
What is atomosphere?
The huge blanket of air by which our earth is surrounded is called atmosphere.
Class 7th Air HBSE Geography Question 2.
Which two gases are found in the atmosphere in abundance?
Name the gases which are found in the atmosphere in lesser quantities?
- Carbon dioxide
Write the percentages of different gases found in the atmosphere.
- Nitrogen : 71%
- Oxygen : 21%
- Carbon dioxide : 0.3%
- Argon : 0.93%
- All others : 0.04%.
Why is stratosphere the most ideal for flying aeroplanes?
Stratosphere is almost free from clouds and associated weather phenomenon, making conditions most ideal for flying aeroplanes.
What is weather?
Hour-to-hour, day-to-day condition of the atomosphere is called weather.
Short Answer Type Questions
Why is atmosphere essential for human beings?
- It provides us the air we breathe.
- It protects as from the harmful rays of the sun.
- It makes the temperature of the earth liveable.
Why is carbon dioxide called a greenhouse gas?
Carbon dioxide traps the heat radiated from the earth arid creates a greenhouse effect. Therefore, it is called a greenhouse gas.
What is global warming?
The quantity of carbon dioxide increases due to factory smoke or car funies and the heat retained increase the temperature of the earth. This called as global warming.
How is ozone gas important to us?
Ozone gas forms a protective layer around the earth it absorbs the harmful ultraviolet radiations of the sun.
Draw diagrams to show (i) Cyclonic rainfall
(ii) Relief rainfall
(iii) Convectional rainfall.
Draw a diagram showing the layers of atmosphere.
Long Answer Type Questions
Explain about different layers of atmosphere.
There are five different layers of atmosphere :
Height : Its average height is about 13 km.
Activities : This is the most important layer of the atmosphere. The air we breathe exists here. All weather phenomena like rainfall, fog and hailstorm occur in this layer.
Upper limit: Tropopause.
Temperature : Not beyond 45°C.
Height: It extends upto a height of 50 km.
Activities: This layer is almost free from clouds and associated weather phenomenon making conditions more ideal for flying aeroplanes. It has the ozone layer which protects us from the harmful affect of rays.
Upper limit: Stratopause.
Temperature : The temperature here keeps on rising.
Height : This is the third layer of the atmosphere. It lies above the height of 80 km.
Activities : Meteorites burn up in this layer on entering the space.
Upper limit: Mesopause.
(iv) Thermosphere : Height: 80-400 km.
Its upper limit satropause
Temperature: The temperature is rising.
Name the various gases in the atmosphere and their functions or uses.
Nitrogen and oxygen are two gases which make up the bulk of the atmosphere. Carbon dioxide, helium, ozone, argon and hydrogen are found in lesser quantities. Apart from these gases, tiny dust particles are also present in the air.
Their functions and uses are as follows:
- Nitrogen is the most plentiful gas in the air. When we inhale, we take some amount of nitrogen into our lungs and exhale it. But plants need nitrogen for their survival.
- Oxygen is the second most plentiful gas in the air. Humans and animals take oxygen from the air as they breathe.
- Carbon dioxide is another important gas. Green plants use carbon dioxide to make their food and release energy.
Which is the greenhouse gas and what affect does it have?
(i) Carbon dixoide-released in the atmosphere creates a greenhouse effect by trapping the heat radiated from the earth. It is therefore called a green house gas and without it the earth would have been too cold to live in. However, when the level in the atmosphere increases due to factory smoke or car fumes, the heat retained increases the temperature of the earth. This is called global warming.
(ii) This rise in temperature causes the snow in the coldest parts of the world to melt.
(iii) As a result, the sea level rises, causing floods in the coastal areas.
(iv) There may be drastic changes in the climate of a place leading to extinction of some plants and animals.
Air Class 7 HBSE Notes
- Atmosphere : Thick blanket of air around the earth.
- Ozone : This thin layer of atmosphere which acts as a filter and absorbs ultra violet radiation.
- Smog: Combination of smoke and fog.
- Stratosphere : Above troposphere it is a cold but clean layer of air.
- Periodic Winds : Winds changing their direction periodically with change in the season.
- Loo : Hot and dry wind that blows over the plains.
- Evaporation : Change of liquid state of water into water vapour.
- Wind : Horizontally moving air near the surface of the earth is called a wind.
- Lapse Rate : The rate at which temperature decreases with altitude is called lapse rate.
- Radiation : Reflection of solar energy by clouds and particles are called radiation.
- Molecule : Smallest particles of a substance in free state.
- Humidity : The amount of water vapour present in the air.
- Insolation : The amount of solar radiations coming down to the earth.
- Terrestrial. Radiation : The heat given off by the earth.