Question

How can be multiple echoes of a single sound be produced ?Explain?

Answer 1

Dear Student,
For our brain to perceive an echo, the echo must be received after a lapse of 0.1 sec
Thus, Minimum distance to be travelled by the sound wave,
d= speed of sound x time
d= 340 x 0.1
d= 34 m
thus sound needs to travel 34 m before reaching our ears again.
Thus, The reflecting surface must be at least (34/2) m away i.e. the .total distance travelled.

For multiple echos, multiple objects should be present at a minimum distance of "17 m" from the source of sound.

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