Question

An echo of a sound is heard after 3 seconds. find the distance of the reflecting surface from the source if the speed of sound in air is 340m/s

Answer 1

d = speed × time , so the speed of sound is 340 m/s and the time is 3 sec. then,
d = 340 × 3 = 1020 m.

the distance is - d = 1020/2 = 510 m answer

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