(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

http://img291.imageshack.us/img291/7829/collisionok5.jpg [Broken]

2. Relevant equations

Conservation of momentum

Conservation of Kinetic Energy

GPE

KE

3. The attempt at a solution

Ive done the first part of the question. With the second part, i thought about it this way:

If the ram is seen to have zero velocity just after impact then all of the rams kinetic energy must have been transphered to the pile, no?

In which case, having worked out the gravitational potential energy in the ram initially to be 5886J. The kinetic energy in the pile must be:

5886 = 0.5 x 300 x V^2

39.24 = V^2

6.26 = V

However apparently the answer *should* be 7.23 m/s.

Can someone tell me where i have gone wrong?

James

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# Homework Help: Dynamics - Another collision question

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