Question

A man fires a gun and hears its echo after 5 s. The man then moves 310 m towards the hill and fires his gun again. This time he hears the echo after 3 s. calculate the speed of sound.

Answer 1

Distance of hill from the man
D1 = velocity x time/ 2 = v × 5 / 2----------------- (equation 1)
Now, D1 − 310 = v × 3 / 2--------------------------- (equation 2)
By subtracting equation 2 form equation 1 ,we get310 = v x (5/2 − 3/2)
So, v = 310m/s