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प्रश्न
In the arrangements A and B shown in the following figure, pins P and Q are fixed to a metal loop and an iron rod with the help of wax. In which case are both the pins likely to fall at different times? Explain.

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उत्तर
In case B, the pin P will fall before the pin Q because the heat will reach pin P first. In case A, the heat travels in both directions and pins P and Q will fall simultaneously.
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