Question

4. Helium balloon floats in warm air (E)
a. Due to contraction of the gas
b. Due to expansion of the gas
c. Due to compression of gas
d. Due to rigidity of gas​

Answer 1

Answer:

Hot-air balloons and blimps can float in the air thanks to buoyancy, an upward force that the air exerts on them. The balloon must weigh less than the air it displaces (the air that would occupy the same space if the balloon wasn't there).

Explanation:

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