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CBSE Class 9 Answered

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.
Asked by | 12 Jan, 2013, 12:41: PM
answered-by-expert Expert Answer

Let the length of the aluminium rod be d.

Speed of sound wave in aluminium at 25°C,

Therefore, time taken by the sound wave to reach the other end,

Speed of sound wave in air at 25°C,

Therefore, time taken by sound wave to reach the other end,

The ratio of time taken by the sound wave in air and aluminium:

Answered by | 12 Jan, 2013, 07:03: PM

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