Question

Tick() the correct answer.
Which of the following is not a characteristic of air?
(a) Air exerts pressure.
(c) Warm air is lighter than cold air,
(b) Air contracts on heating
(d) Air has weight.
2. Which of the following play(s) a major role in the formation of a thunderstorm
(a) Conduction
(b) Convection
(c) Radiation
(d) Conduction and radiation
3. Which of the following should not be done during a thunderstorm?
(a) Getting into a car
(b) Getting out of water and going inside a building
(c) Taking shelter under an umbrella with a metallic end
(d) Shutting windows and doors tightly
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Answer 1

Answer:

1-c

2-b

3-c

here it is your answers

Answer 2

The above questions are answered below:

1. (b) Air contracts on heating- is not a characteristic of air

Upon heating, the air expands and not contracts as given.

Air exerts pressure which is called atmospheric pressure.

In warm air, the air particles are spaced more as compared to cold air. Hence, it is lighter.

As air has mass, it has weight too.

2. (b) Convection plays a major role in the formation of a thunderstorm.

As the air heats up owing to sunlight, the warm air rises up as it is lighter than the cold air. This method of heat transfer is called convection. Air cannot exhibit conduction as it is fluid and conduction is possible only in solids.

3. (c) Taking shelter under an umbrella with a metallic end - should not be done during a thunderstorm.

During thunderstorm, there is a possibility of striking of lightening. As lightening is electricity, it can conduct through the metal end of umbrella.

So, this should be totally avoided.