NCERT Class 7 Geography Chapter 4 Question Answers from the chapter water. NCERT Class 7 Geography Chapter 4 Question Answers are simplified, precise, and easy to understand.
NCERT Class 7 Geography Chapter 4 Question Answers
Answer the following questions.
1. What is atmosphere?
Answer: The atmosphere is a thin blanket of air surrounding the Earth. Several gases like Nitrogen, Oxygen, Carbon Dioxide, etc. are part of the atmosphere. It protects us from the harmful rays of the sun.
2. Which two gases make the bulk of the atmosphere?
Answer: Nitrogen (78%) and Oxygen (21%).
3. Which gas creates greenhouse effect in the atmosphere?
Answer: Carbon Dioxide.
4. What is weather?
Answer: Change in the atmospheric conditions for a short period of time is called weather.
5. Name three types of rainfall?
Answer:
(1) Cyclonic Rainfall
(2) Orographic (Relief) Rainfall
(3) Convectional Rainfall
6. What is air pressure?
Answer: The force exerted by the weight of air on the earth’s surface is known as air pressure.
Tick the correct answer.
1. Which of the following gases protects us from harmful sun rays?
(A) Carbon dioxide
(B) Nitrogen
(C) Ozone
2. The most important layer of the atmosphere is
(A) Troposphere
(B) Thermosphere
(C) Mesosphere
3. Which of the following layers of the atmosphere is free from clouds?
(A) Troposphere
(B) Stratosphere
(C) Mesosphere
4. As we go up the layers of the atmosphere, the pressure
(A) Increases
(B) Decreases
(C) Remains the same
5. When precipitation comes down to the earth in the liquid form, it is called
(A) Cloud
(B) Rain
(C) Snow
Match the following.
| (1) Trade Winds | (e) Permanent |
| (2) Loo | (f) Local Wind |
| (3) Monsoon | (b) Seasonal WInd |
| (4) Winds | (c) Horizontal movement of Air |
Give reasons.
1. Wet clothes take longer to dry on a humid day?
Reason:
On a humid day, the air is full of water vapor and its moisture-carrying capacity is less. Hence, evaporation is very slow. This is the reason why wet clothes take a longer time to dry on a humid day.
2. Amount of insolation decreases from the equator towards the poles?
Reason:
On the Equator, sunrays are straight and direct. Heating is more in the equatorial areas.
Near the poles, sunrays are slanting. Heating is less in the polar regions.
Thus, the amount of insolation decreases from the equator toward the poles.