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Runner1 is going 20 degrees NofE with a mass of 60kg and v=5m/s. Runner2 is going 20 degrees NofW with a mass of 80kg and v=4m/s when they collide. What are their respective momentums prior to the collision? What is their final velocity and direction after collision if it was perfectly inelastic collision?

For question1 I got L=300kgm/s for runner1 and L=-320kgm/s for runner2.

For question2 I'm a little perplexed. This is what I did.

(x) m1v1+m2v2=(m1+m2)vf

-4sin20(80kg)+5sin20(60kg)=(60kg+80kg)vf

-109+103=140vf

-6=140vfx

vf(x)=-.049m/s

(y) m1v1+m2v2=(m1+m2)vf

4cos20(80kg)+5cos20(60kg)=(60kg+80kg)vf

301+282=140vf

583=140vf

vf(y)=4.16m/s

Then I took the TAN-1(4.16/-.049) to find theta and it gave me -89degrees North of East.

Does this look right?

Thank you to anyone who can give me some insight. I appreciate your help.

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# Homework Help: Looking for verification on a momentum & collision problem

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