NCERT Solutions for class 7 science Chapter 8

Winds, Storms and Cyclones

NCERT Solutions for Class 7 Science chapter 8 Exercise Question

Question 1

Fill the missing word in the blank spaces in the following statements:

(a) Wind is——————air.

(b) Winds are generated due to——————heating on the earth.

(c) Near the earth’s surface __________air rises up whereas ___________ air comes down.

(d) Air moves from a region of ——— pressure to a region of——— pressure.

Answer

(a) Wind is moving air.

(b) Winds are generated due to uneven heating on the earth.

(c) Near the earth’s surface, warmair rises up whereas cold air comes down.

(d) Air moves from a region of high air pressure to a region of low air pressure.

Question 2

Suggest two methods to find out wind direction at a given place.

Answer

Methods to finding out the wind direction at a given place are as follows

i. By using a device called anemometer.

ii Toss a light paper and observe it will flow in the direction of blowing wind .

Question 3

State two experiences that made you think that air exerts pressure (other than those given in the text).

Answer

i.When we fill a balloon with air it becomes tight which proves air exerts pressure.

ii. When we try to stand against a strong air we aren't able to stand this saw air exerts pressure

Question 4

You want to buy a house. Would you like to buy a house having windows but no ventilators? Explain your answer.

Answer

A house having no ventilators should not be bought. This is because warm air is lighter than cold air so it rises up easily . If there are no ventilators, then the warm air cannot go out easily.

Question 5

Explain why holes are made in hanging banners and hoardings.

Answer

As air exert pressure and fast blowing air able to tear them off that why holes are creat in the banners and hoardings which helps air to pass through it..

Question 6

How will you help your neighbours in case cyclone approaches your village/town?

Answer

We can help our neighbours in case a cyclone by any of the following :

i)We helping them shifting their animals ,necessary households and vehicles to a safer place.
ii)We can help by provide phone numbers of all emergency services or calling such services like police and medical centres etc .

Question 7

What planning is required in advance to deal with the situation created by a cyclone?

Answer

• we have to vary carefully listening the warnings telecast on T.V and radio.
• We should move to safer places;
• Keeping an emergency the phone numbers of all emergency services like police, medical and kit ready.
• Store food and drinking water for emergencies.
• Not venturing into sea.
• We should help our neighbours and friends.

Question 8

Which one of the following places is unlikely to be affected by a cyclone?

(i) Chennai

(ii) Mangaluru (Mangalore)

(iii) Amritsar

(iv) Puri

Answer

iii) Amritsar

Question 9

Which of the statements given below is correct?

(i) In winter the winds flow from the land to the ocean.

(ii) In summer the winds flow from the land towards the ocean.

(iii) A cyclone is formed by a very high-pressure system with very high-speed winds revolving around it.

(iv) The coastline of India is not vulnerable to cyclones.

Answer

(i) In winter, the winds flow from the land to the ocean.