Question

a bullet leaves a rifle with a velocity of 100m/s and the rifle of mass 2.5 kg recoils with a velocity of 1m/s.find the mass of the bullet.

Answer 1

Hello!

Conservation of Momentum :

m₁v₁ = m₂v₂

⇒ m₁ = m₂v₂ / v₁

⇒ m₁ = (2.5 × 1) / 100

⇒ m₁ = 0.025 kg

⇒ m₁ = 25 g

Cheers!

Answer 2

ANSWER :-
Applying the conservation of momentum to the problem we get,

==>m1v1 = m2v2(where m1v1 and m2v2 are the momentums of the bullet and rifle respectively)

=>m1 = m2v2 / v1
=>m1 = (2.5 * 1) / 100
=>m1 = 0.025kg
=>m1 = 25g
==>Mass of bullet is 25g.