CBSE Class 9 Answered

Dear student,

The basis of how the balloon works is that warmer air rises in cooler air. This is because hot air is lighter than cool air as it has less mass per unit of volume. Mass can be defined by the measure of how much matter something contains. The actual balloon (called an envelope) has to be so large as it takes such a large amount of heated air to lift it off the ground. For example, to lift 1000 pounds worth of weight you would need almost 65,000 cubic feet of heated air! To help keep the balloon in the air and rising, hot air needs to be propelled upwards into the envelope using the burner.

A hot air balloon is made up of 3 main parts:

• The Envelope
  The actual fabric balloon which holds the air
• The Burner
  The unit which propels the heat up inside the envelope
• The Basket
  Where the passengers  stand

We hope this helps.

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