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Question
A man standing 25 m away from a wall produces a sound and receives the reflected sound.
- Calculate the time after which he receives the reflected sound if the speed of the sound in air is 350 m/s-1.
- Will the man be able to hear a distinct echo? Explain the answer.
Solution
- d = 25 m;
t = ?
v = `(2d)/t`
t = `(2d)/v`
= `(2 xx 25)/350`
= `1/7` sec. - Yes, as t= 0.143 s, and original sound persists only for 0.1 s.
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