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## Homework Statement

http://home.phys.ntnu.no/brukdef/undervisning/tfy4145/ovinger/Ov10.pdf

Look at the picture in "oppgave 1".

Suppose you have an incoming mass which hits the very thin rod straight on in a completely inelastic collision. the incoming mass is ##m##, the rod has a mass of ##M##, and the little mass hits the rod at a length ##l## from the top.

According to the text, the linear momentum right before and right after are NOT preserved, while the angular momentum is.

## The Attempt at a Solution

I calculated the total linear momentum before and after, and indeed I got:

[tex] p_0 = m v[/tex]

and

[tex] p_1 = \frac{m v + M L/2l}{MvL^2 /3ml^2 +1}[/tex]

so the two momentums are seemingly unpreserved. Why is this so? I realize it's a translational motion going over to a rotational one, but what does this have to do with linear momentum not being preserved??

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