Question

A person observe the smoke from a gun 1.4 sec before he hear the bang. If the gun is 476m away from the person, find the speed of sound.

Answer 1

Speed of light =$3\times {10}^{8}m/s$
speed of sound =v
Time taken b y light to travel 476 m
$=\frac{476}{3\times {10}^8}sec$
Time taken by sound to travel 476 m = $\frac{476}{v}sec$.
Given: $\frac{476}{v}-\frac{476}{3\times {10}^8}=1.4$
By solving for "v", we get the value:
v= 340 m/s