# Bullet, Pendulum Questions

#### pauln

1. The problem statement, all variables and given/known data

A 10g bullet moving at 300 m/s hits and passes through a 2.2 kg pendulum target. After impact the 1.2 m long pendulum rises up an angle of 15 degrees. Find the final speed (Vf) of the bullet.
http://img233.imageshack.us/img233/7566/34494449gz4.png [Broken]
2. Relevant equations
sigma(P)=sigma(P')
sigma(E)=sigma(E')

3. The attempt at a solution

i have no idea where to begin

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#### Dick

Homework Helper
Use conservation of momentum to find the initial velocity (hence initial kinetic energy of the pendulum) in terms of Vf. Take the change in potential energy of the pendulum during to swing to figure out what the initial kinetic energy was. Now solve for Vf. DO NOT attempt to conserve kinetic and potential energies throughout the problem. The collision itself is inelastic. Got that? Now get started.

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