Consider a bullet of mass m fired at a speed of V0 into a wooden block of mass M. The bullet instantaneously comes to rest in the block. The block with the embedded bullet slides along a horizontal surface with a coefficient of kinetic energy [tex]\mu[/tex].
How far does the block slide before it comes to rest? Express your answer in terms of m, M, [tex]\mu[/tex] and g.
W = Fs
W = KEf - KE0
where s = displacement
The Attempt at a Solution
I started by saying W = Fs and thought the only net force working here is kinetic friction.
so W = FN [tex]\mu[/tex] s and since FN = mg i said...
W = (m +M)g [tex]\mu[/tex]s
then i said since W = KEf - KE0 ....
(m + M)g[tex]\mu[/tex]s = KEf - KE0
is this the right appoach?
I cant use conservation of momentum since the sum of external forces arent 0, im assuming since they give the coefficient of kinetic friction.