Question

from a rifle mass of 4 kg a bullet of mass 50 gram is fired with an initial velocity of 5 m/s square.
calculate the recoil velocity of rifle

Answer 1

Since no external force acts on the rifle, the change in momentum is zero.

Mometum of rifle = Momentum of bullet.

4 x V = 0.050 x 35

V = 0.44 m/s.

This is the recoil velocity of rifle.

Answer 2

By using conservation of momentum equation

Recoil velocity of rifle = m1u1 / (m1 + m2)
= 50 * 10^-3 * 5 / [(50 * 10^-3) + 4]
= 0.06 m/s