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Question
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Solution
A simple method for finding the velocity of sound is echo or open air method.
For example: A person stands at a known distance (d m) from a cliff and fires a pistol and simultaneously starts the stop watch. He stops the stop-watch as soon as he hears the echo. The distance traveled by sound during this time (t seconds) is twice the distance (2d m). The velocity (v) of sound is then calculated as under:
Velocity of sound= `"distance travelled"/" time taken" = (2"d")/"t"`
By repeating the experiment two or three times, the average velocity of sound can be calculated.
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