Question

A machine gun has a mass of 20 kg. It fires 30 g bullets at the rate of 400 bullets per second with a speed of
400 ms–1. What force must be applied to the gun to keep it in position?

Answer 1

Answer:

YOUR QUESTION :

A machine gun has a mass of 20 kg. It fires 30 g bullets at the rate of 400 bullets per second with a speed of 400 ms–1. What force must be applied to the gun to keep it in position?

YOUR ANSWER :

The force must be applied to the gun to keep it in position is 4800 N.

ANSWER EXPLANATION :

Given :

A machine gun has a mass of 20 kg. It fires 30 g bullets at rate of 400 bullets per second with a speed of 400 m/s.

To find :

What force must be applied to the gun to keep it in position?

Solution :

Mass Of Machine Gun m= 20 kg

Mass of each Bullet, M=30 g=0.030 kg

Velocity Of Bullet v=400 m/s

No. of Bullets = 400

Let V be the recoil velocity,

$v = \frac{mv}{m} \\ = > v = \frac{0.030 \times 400}{20}$

v = 0.6 m/s.

Time taken to fire on bullet is

$t = \frac{1}{400} seconds$

The force must be applied to the gun to keep it in position is

$f = \frac{mv}{t} \\ = > f = \frac{20 \times 0.6}{ \frac{1}{400} } \\ = > f = 20 \times 0.6 \times 400 \\ = > f = 4800n$

Therefore, The force must be applied to the gun to keep it in position is 4800 N.