Momentum Conservation and Collisions Concept?

AI Thread Summary
In a collision between a 100 kg man running and a 90 kg man walking, the momentum of the system is conserved overall, meaning the total momentum before and after the collision remains constant. However, the individual momentum of the 100 kg man may change depending on the nature of the collision, which can cause his velocity to decrease. The confusion arises from the distinction between total momentum conservation and individual momentum changes during collisions. In elastic collisions, while total momentum is conserved, individual momenta can vary due to interactions. Understanding this principle clarifies the dynamics of momentum in collisions.
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Homework Statement


A 100 kg man and a 90 kg man are rounding a corner and collide. The heavier man is running, while the 90 kg man is walking. What happens to the momentum of the 100 kg man? Does it increase, decrease, stay the same, or "is conserved"?


Homework Equations


Change in momentum = MV(final) -- MV(initial)


The Attempt at a Solution


Out of the multiple choice answers, I would think that his momentum would decrease because his velocity is decreasing, but I know that in such elastic collisions, momentum is ALWAYS conserved. This is why I'm confused. Any explanation would be greatly appreciated! :)
 
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The total momentum is conserved. All the individual momenta are, generally, not or collisions wouldn't change anything!
 
Thank you very much!
 
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