A hot air balloon is flying in air. It comes down long after the burner is switched off. Explain why? Name and state the principle used.

Asked by vatsalchoudhary41 | 27th Feb, 2015, 03:27: PM

Expert Answer:

A hot air balloon works because the hot air causes it to lift. This is due to buoyancy. Hot air is lighter than cold air. So, there is a net buoyant force in the upward direction.
Now, when the engines are switched off, the amount of hot air starts reducing, but it is still present inside the balloon. So, the balloon reaches ground after a long time.
Buoyancy is defined as the tendency of a fluid to exert an upward force on any object present in it.

Answered by Romal Bhansali | 27th Feb, 2015, 04:53: PM

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