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A lighted candle is placed inside a rect...

A lighted candle is placed inside a rectangular box having two holes at its top, and a wheel made up of paper is placed inside it as shown in figure. In which direction will the wheel rotate? Why?

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Due to the lighted candle, the air above it gets heated up. Then it expands and becomes lighter, and hence goes up. When hot air moves in the upward direction through hole B, fresh air enters through the hole A. So, it creates a air current or wind from A to B. So, the wheel starts rotating in clockwise direction.
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