Question

A bullet of mass 25 g is fired from a rifle of mass 2 kg. Imagine that no other forces are acting on the system. If the bullet travels with a velocity of 2 ms^-1 , what will be the velocity of the recoil of the rifle?

Answer 1

Momentum of the rifle = momentum of the bullet 

Mass of the rifle × velocity of recoil 

= mass of the bullet × Velocity of the bullet 

2 × velocity of recoil = \(\frac{25}{1000} \times 2\)

2 × velocity of recoil =\(\frac{1\times2}{40} = \frac{1}{20}\)

velocity of recoil =\(\frac{1}{2} \times \frac{1}{20}= \frac{1}{40}\)

= 0.0025 ms^-1.