A large wooden wheel of radius R and the moment of inertia I is mounted on an axle so as to rotate freely. A bullet of mass m and speed v is shot tangential to the wheel and strike its edge, lodging in the wheel’s rim. If the wheel was originally at rest, what is its rotation rate just after the collision?

1 answer

Initial angular momentum about axis =
Mbullet*Vbullet*R

This equals the final angular momentum,
(Iwheel + Mbullet*R^2)*w_final

w_final = (Mbullet*Vbullet)*R/(Iwheel + Mbullet*R^2)