Question

A gun of mass 3 kg fires A bullet of mass 30 g. The gun takes 0.003 seconds to move to the barrel of the gun and acquires a velocity of 100m/s. Calculate :-
a) the velocity with which the gun recoils
b) the force exerted on Gunman due to record of the gun.

Answer 1

Use conservation of momentum
M¹V¹ =M²V²
=> mass of gun = 3 kg

mass of bullet = 30 g = 0.03 kg

3 * u = 0.03 * 100

3u = 3

u = 1m/s

Gun will recoil at 1m/s

We know v= u +at

100 = 0 + a * 0.003

100/0.003 = a

acceleration of bullet = 100/0.003 m/s2

mass of bullet = 0.03kg

Force = ma

= 100/0.003 * 0.03

=1000N