so i have a question about work and impulse:(adsbygoogle = window.adsbygoogle || []).push({});

The diagram shows an overhead view of two pucks on a frictionless air track. Puck 1 has a mass of 8 kg and puck 2 has a mass of 10.3 kg. The pucks begin at rest at the starting line. The pucks are pushed across the table by equal forces as a function of distance until they reach the finish line. Answer the following three questions about the pucks.

1) Which puck has larger kinetic energy?

A) 1, B) 2, C) same, D) unable to be determined

2) Which puck will cross the finish line first?

A) 1, B) 2, C) same, D) unable to be determined

3) Which puck has larger momentum?

A) 1, B) 2, C) same, D) unable to be determined

So, I know that the puck with smaller mass will cross the finish line first, which is puck 1, so the answer to question 2 is A.

My problem is, I've reasoned that should the same force be applied, the momentums would be equal, because although one has larger mass, the velocities will balance out, so equal momentums. The puck with larger kinetic energy would be the lighter puck for hte same reason.

This is not correct, and I can't really figure out why.

I know this is more of a conceptual question and harder to figure out with just straight math, so any help in the right direction would be much appreciated.

Thanks,

TwiztidMxcn

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# Homework Help: Work and impulse question

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