1. The problem statement, all variables and given/known data Person A fires a 222 g arrow towards an archery target at a speed of 109 m/s. Person B shoots a 190. g arrow moving in the same direction. This arrow moves with a speed of 290. m/s, catches up, and then collides with Person A's arrow. If the arrows collide in a perfectly elastic manner, what will be the magnitude of velocity of Person B's arrow afterwards? 2. Relevant equations Conversation of Momentum m1v1+m2v2=m1v1'+m2v2' 3. The attempt at a solution So far, I tried doing: m1v1+m2v2=m(1+2)vf' (0.222)(109)+(0.190)(290)=(0.222+0.190)vf' And solved for vf. but it isn't the correct answer. I also tried Conversation of Kinetic Energy 1/2(0.222)(109)^2+1/2(0.19)(290)^2=1/2(0.412)v^2 And solved for vf. but it isn't the correct answer. What am I doing wrong?