Here is the problem: 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.