A gun is fired from a place which is at distance 1.2 km from a hill. The echo of the sound s heard back at the same place of firing after 8 second. Find the speed of sound.

Explanation

The goli moves like a projectivel.
Here, h= 0.196 m ltbgt Horizontal distance , x= 2m
Acceleration, g= 9.8 m/s^2
Time to reach the ground
`t= sqrt(2h)/g= sqrt(2xx0.196)/9.8)
`= 0.4=0.2 sec`
Let horizontal velocity with which it is projected be u m/s

`:.=x=ut
`x=ut`
rarr = (x/t)= (2/0.2)= 10 m/s`