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Question
Take a sheet of paper. Draw a spiral on it as shown in Figure. Cut out the paper along the line. Suspend the paper as shown in Figure above a lighted candle. Observe what happens. Think of an explanation.
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Solution
Here is the observation and explanation for the given activity:
Observation: When you cut out the spiral from the paper and suspend it above a lighted candle, the spiral begins to rotate.
Explanation: The heat from the candle flame warms the air around it, causing it to rise. This rising warm air creates a convection current. When the paper spiral is placed above the candle, the rising warm air hits the spiral and causes it to spin. This is because the moving air applies a force to the spiral, making it rotate.
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