# Inelastic collision question

1. Nov 6, 2004

### AeroFunk

A 16 g bullet strikes and becomes embedded in a 1.30 kg block of wood placed on a horizontal surface just in front of the gun. If the coefficient of kinetic friction between the block and the surface is 0.22, and the impact drives the block a distance of 8.5 m before it comes to rest, what was the muzzle speed of the bullet?

Is there anthor equation i can use besides the conservation of momentum
mv=(m+M)v' I can't use conservation of energy because its inelastic right? So what can I do help please.

2. Nov 6, 2004

### Pyrrhus

Kinematic:

$$v^2 = v_{o}^2 + 2a \Delta x$$

and Newton's 2nd Law to get the acceleration

$$\sum_{i=1}^{n} \vec{F}_{i} = m \vec{a}$$

3. Nov 13, 2004

### lurflurf

You can't use conservation of kinetic energy.
Use can use conservation of energy.

4. Nov 13, 2004

### arildno

1. Assume that after the collision is finished, the system begins moving with some velocity $$v_{0}$$
Determine $$v_{0}$$ with Cyclovenom's first equation.