Question

Fill the missing word in the blank spaces in the following statements: [4 marks]

(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 1

(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 pressure to a region of low pressure.

Let's discuss each:

(a) Wind is moving air and is caused by differences in air pressure within our atmosphere. [1 mark]

(b) Since the earth's surface is made of various land and water formations, it absorbs the sun's radiation unevenly. And as we already discussed, the wind is nothing but air in motion. Thus, winds are produced by uneven heating of the earth’s surface by the sun. [1 mark]


(c) The movement of air is mainly caused by the differences in pressure and temperature. Warm air is lighter and it rises upwards, meanwhile, cold air is denser and hence it moves down to replace the warm air. This phenomenon creates wind.
So, near the earth’s surface, warm air rises up whereas cold air comes down. [1 mark]


(d) Air always moves from a region of high air pressure to a region of low air pressure. [1 mark]