Question

Hot air is lighter than cold air. Justify

Answer 1

• When air gets heated up it expands and becomes less dense than the air surrounding it.
• As shown in the image above after getting hot the distance between the air molecules increased by considerable amount.
• So hot air is less dense than cold air.
• Now the less dense air floats in the much denser air just like ice floats on water as ice is less dense than water.
• A similar example of wood floating on water can also be taken into account.
• Wood is solid and less dense hence, it floats on water.
• Therefore, hot air is lighter than cold one.