Question

A 20 g bullet is fired horizontally with a velocity of 250 m/s from a 1.5 kg rifle. If the rifle was held loosely, what would be the recoil velocity?

Answer 1

Answer:

3.33 m/s

Explanation:

given,

mass of bullet, m = 20 g = 0.02 Kg

speed of bullet, v = 250 m/s

mass of rifle, M = 1.5 kg

speed of recoil, u = ?

initial speed of the bullet and the rifle is zero.

using conservation of momentum

(M + m) V = m v +  M u

(M + m) x 0 = 0.02 x 250 +  1.5 x u

 1.5 u = -5

   u = -3.33 m/s

negative sign represent that the recoil velocity is opposite to bullet velocity.

Hence, the recoil velocity is equal to 3.33 m/s