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Question
Describe a simple experiment to determine the speed of sound in air. What approximation is made in the method described by you?
Solution
The simple experiment that a person can do to calculate the speed of sound in air is that a person stands at a known distance (d meter) from the cliff and fires a pistol and simultaneously start the stopwatch. He stops the stopwatch as soon as he hears an echo. The distance travelled by the sound during the time (t) seconds is 2d. So, speed of sound = distance travelled / time taken = 2d/t
The approximation made is that speed of sound remains same for the time when the experiment is taking place.
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