NCERT Solutions for Class 7 Science Chapter 8 – Winds, Storms and Cyclones Exercise Questions

(a) Wind is moving air.

 

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

 

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

 

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

 

The two methods to finding out the wind direction at a given place are as follows:

 

i. By seeing the direction of dry leaves released in the air.

 

ii By seeing the direction in which it is difficult to ride the bicycle.

 

i. When we fill the air in the balloon, it becomes tight, and if we try to fill more air, the balloon will burst which proves air exerts pressure.

 

ii. Wind causes curtains, doors and windows to move with the direction of the wind. This demonstrates air exerts pressure.

 

It is not a good idea to buy a house without ventilators because warm air is lighter than cold air hence warm air passes out of your home through ventilators. Accordingly, without ventilators, warm air will not pass out, and the house will remain warm.

 

Holes in the banners and hoardings help air to pass through them. Hence, banners can withstand the pressure of the air and remains intact.

 

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

 

• By helping them shift to a safer place.

 

• By helping them to shift their animals, necessary households and vehicles to a safer place.

 

• By calling emergency services such as fire stations, police, medical centres etc.

 

 

• We should not ignore the warnings issued by the meteorological department through TV, radio, or newspapers.

 

• We should make necessary arrangements to shift the essential household goods, domestic animals and vehicles, etc., to safer places.

 

• Avoid driving on roads through standing water, as floods may have damaged the roads.

 

• Phone numbers of all emergency services like police, fire brigade, and medical centres should be handy.

 

• Always store drinking water for emergencies.

 

• Do not touch wet switches and fallen power lines.

 

• Do not pressurise the rescue force by making undue demands.

 

• Cooperate and help your neighbours and friends.

 

(iii) Amritsar because Amritsar is far away from the sea, while the remaining three are coastal areas and are more likely to be hit by a cyclone.

 

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