Wood Movement Due to Rubber vs. Aluminum Bullet Impact: Explanation

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The discussion centers on the impact of rubber and aluminum bullets on wood blocks. The rubber bullet, upon impact, transfers nearly all its momentum to the wood and bounces back, resulting in greater movement of the wood. In contrast, the aluminum bullet burrows into the wood, retaining some of its momentum and causing less movement. The consensus is that the rubber bullet causes the wood to move faster due to its complete momentum transfer. The explanation highlights the differences in momentum transfer between the two materials.
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two bullets of eqaul mass are shot at equal speeds at blocks of wood on a smooth ice rink. one bullet, made of rubber, bounces off the wood. the other bullet, made of aluminum, burrows into the wood. which bullet makes the wood move faster? why?

i said the rubber bullet will make the wood move faster, because it will transfer almost of it intial momentum to the wood. can some one please tell me if I'm right or way off thanks.
 
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butz3 said:
i said the rubber bullet will make the wood move faster, because it will transfer almost of it intial momentum to the wood. can some one please tell me if I'm right or way off thanks.

It's the rubber bullet, and you seem to have the right idea, but I'm not sure that your explanation is very good.
 
Basically, youre right:
The rubber bullet will not only transfer ALL it's initial momentum, it will also gain momentum in the opposite direction.
Hence, the momentum of the block will be greater or equal than the initial momentum of the rubber bullet.

The other bullet retains some of it initial momentum; hence, the resulting momentum of the block will be less than orequal to the initial momentum of the bullet..
 
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