﻿ A machine gun is mounted on a tank moving at a speed of 20 ms–1towards a target with the gun pointing in the direction of motion of the tank. The muzzle speed of the bullet equals the speed of sound = 340 ms–1. If, at the time of firing, the target is 500 m away from the tank, then   : Kaysons Education

# A Machine Gun Is Mounted On A Tank Moving At A Speed Of 20 Ms–1towards A Target With The Gun Pointing In The Direction Of Motion Of The Tank. The Muzzle Speed Of The Bullet Equals The Speed Of Sound = 340 Ms–1. If, At The Time Of Firing, The Target Is 500 M Away From The Tank, Then

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## Question

### Solution

Correct option is

The sound arrives at the target later than the bullet

Since only the source of sound, i.e. the gun is in motion, the speed of sound remains unchanged at 340 ms –1. Therefore, the time taken by the sound of firing to arrive at the target 500 m away is

If the gun points in the direction of motion of the tank, the effective speed of the bullet = 340 + 20 = 360 ms–1. Therefore the time taken by the bullet to reach the target is

Since ts > tb.

Testing

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