Question

A bullet with a mass of 0.3 kg is fired out of a gun with a mass of 4 kg at 600 m/s. What is the recoil velocity on the gun?

200 m/s
45 m/s
2400 m/s
90 m/s

Answer 1

According to the Conservation of Momentum,

Momentum of the gun = momentum of the bullet

M(gun)×V(gun)=m(bullet)×v(bullet)

4kg × V = 0.3kg × 600m/s²

V = (0.3 × 600)/4 = 45 m/s

The recoil velocity on the gun is 45 m/s

45 m/s is the right answer.