Question

a bullet of mass 0.06kg is fired into a block of wood. if the bullet is moving at 330 m/s as it enters the block and takes 0.15m to stop, find:

A) the avg force required to stop the mullet
b) the impulse exerted by the wood on the bullet
c)change in momentum of bullet

Answer 1

1. (avg. force)*(stopping distance) = (initial kinetic energy) = (1/2) M V^2
Solve for the initial force.
The statement says that the work done frictionally heating the wood equals the in initial kinetic energy.

2. Impulse = -(intial momentum) = -M V

3. Change in momentum = -(Initial momentum) = -M V

They may not care about the minus signs in the last two.