# Ballistic Pendulum

#### bobbles22

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

A bullet (mass m, velocity v) is fired into a suspended wooden block (mass M) which then rises up to height h with the bullet embedded within it. Find, in terms of m, M and H, the proportion of the initial kinetic energy of the bullet that is transferred to mechanical energy of the pendulum. What happened to the rest of the energy.

2. Relevant equations

Kinetic energy = 0.5mv2

Gravitiational potential energy = mgh

3. The attempt at a solution

Obviously, the initial kinetic energy is 0.5mv2. I've worked out v from a previous part of the question to be v=(2gh)0.5(1+M/m). But I'm stumped as to how to find the proportion of the energy that is transferred as mechanical energy to the block. Obviously, the difference of energies before and after the impact are due to loss of energy during the impact to thermal and sound energy.
1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

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"Ballistic Pendulum"

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