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Question
How can you calculate the speed of sound using echo?
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Solution
Apparatus required:
A source of sound pulses, a measuring tape, a sound receiver, and a stopwatch.
Calculation of speed of sound:
The sound pulse emitted by the source travels a total distance of 2nd while travelling from the source to the wall and then back to the receiver.
The time taken for this has been observed to be ‘t’. Hence, the speed of the sound wave is given by:
Speed of sound = `"Distance travelled"/"Time taken"` = `(2"d")/"t"`
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