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Question
Hot air balloons float in the air because of the low density of the air inside the balloon. Explain this with the help of an appropriate gas law.
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Solution
The working of a hot air balloon can be explained with the help of Charles’ law. According to Charles’ law, at constant pressure, the volume of a fixed amount of a gas varies directly with the temperature. This means that as the temperature increases, the air inside the balloon expands and occupies more volume. Thus, hot air inside the balloon is less dense than the surrounding cold air. This causes the hot air balloon to float in the air.
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