A girl is sitting in the middle of a park of dimension 12 m 12 m On the left side of it there is a b...

Question

A girl is sitting in the middle of a park of dimension 12 m 12 m On the left side of it there is a building adjoining the park and on right side of the park there is a road adjoining the park A sound is produced on the road by a cracker Is it possible for the girl to hear the echo of this sound Explain your answer

Accepted Answer

Echo can be heard if the gap between the original sound and reflected sound received by the listener is around 0.1 sec.

Sound Velocity× time interval

=344×0.1

= 34.4 m

Here sound reflects from the building and then reaches the girl which is much smaller than the required distance.

Hence echo cannot be heard.

NCERT Exemplar Solutions Class 9 Science Solutions for Sound - Exercise in Chapter 12 - Sound