Question

Megan fires an 8 kg rifle which uses a 0.05 kg bullet with a muzzle velocity of 500 m/s. What is the recoil velocity of the rifle?

Answer 1

To calculate the recoil velocity of the rifle, we can use the principle of conservation of momentum. According to this principle, the total momentum before the rifle is fired is equal to the total momentum after the rifle is fired.

Let's denote the recoil velocity of the rifle as V. The total momentum before the rifle is fired is zero, as both the rifle and the bullet are stationary. After the rifle is fired, the total momentum of the system (rifle + bullet) will be conserved.

Initial momentum of the system = Final momentum of the system

(0) = (mass of the rifle) * (final recoil velocity of the rifle) + (mass of the bullet) * (final velocity of the bullet)

(0) = (8 kg) * V + (0.05 kg) * (500 m/s)

Now we can solve for V, the recoil velocity of the rifle:

(8 kg) * V = - (0.05 kg) * (500 m/s) (since the bullet is moving in the opposite direction to the recoil)

V = - (0.05 kg * 500 m/s) / (8 kg)

V = -3.125 m/s

So the recoil velocity of the rifle is approximately -3.125 m/s. The negative sign indicates that the rifle moves in the opposite direction to the bullet when fired.

double check this aswell pls :D