A student stands at a distance 400m from a wall and claps two pieces of wood. After the first clap the student claps whenever an...

A student stands at a distance 400m from a wall and claps two pieces of wood. After the first clap the student claps whenever an echo is heard from the wall. Another student starts a stopwatch at the first clap and stops it after the twentieth clap. The stopwatch records a time of 50 seconds. Find the speed of sound.

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20 claps equal 50 secs
1 clap
We cross multiple
1 clap×50claps / 20 claps
So 1 clap takes 2.5 secs
For one to hear an echo sound will travel up to the wall then back hence travellings 400×2=800metres
From our formulae distance=speed×time
800=s×2.5
Hence speed=800/2.5
=320m/s

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Rootz answered the question on October 28, 2017 at 18:22

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