Q.8. Two children are at opposite ends of an aluminium rod. One strikes the end of the rod with a stone. Find the ratio of times taken by the sound wave in air and in aluminium to reach the second child.
(Given: Speed of sound in air is ; Speed of sound in aluminium is )
Here, let us assume the length of the rod be .
Then,
Time taken by the sound wave in air:
Time taken by the sound wave in Aluminium to reach from one end to the other end,
Therefore, the ratio of the time taken by the sound wave in air and in aluminium will be:
Hence, the ratio is .
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