Question

A man fires a gun towards a hill and hears the echo after 5 sec. he then moves 340m towards it and fires the gun again. this time he hears the echo after 3 sec. calculate the speed of the sound

Answer 1

It takes 5 seconds for the sound to go to the hill and come back. Thus, it took 2.5 seconds to reach the hill. After the man moved, this was reduced by 1 second to 1.5 seconds. Thus the speed of sound is 340m per second.

Answer 2

Initially sound travels for 5 sec
Finally it travels for 3 sec after moving towards the hill 340m
So,sound has to travel less =340*2 m
=680 m in ( 5-3) =2 sec
The velocity =680/2 m/s
=340 m/s