Q17 of 50 Page 12

The flash of a gun is seen by a man 3 seconds before the sound is heard. Calculate the distance of the gun from the man (Speed of sound in air is 332 m/s).

Since the speed of lght is 3*108, for all the purpose, the flash is seen at the same time that the gun is fired.

So we know that formula of speed= distance/time;


So, distance= speed*time (i)


Sped of sound in air is 332 m/s (given) and time= 3s.


Subustituing the value in equation (i) we get


(D)= 332 m/s*3s


We get D= 996 m.

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