For the first picture: Would the velocity of B equal mvsin60 deg (All the horizontal velocity) It is originally at rest. ----- 92 (30 min exams) If the 2 objects shown below collide and remain together without spinning what will be their final velocity Answer: 5.8 m/s The horizontal momentum of the 2 rock system equals zero so there will be no horizontal velocity. The vertical momentum is 87 kg m/s We divide this by 15 kg to get 5.8 m/s --------- Photos of each are in an attachment. I really don't understand how horizontal (left to right) velocity is zero. Something is not clicking for me because I see that the ball is going in a diagonal direction. Do the 2 horizontal velocities cancel out? Or is there no horizontal velocity at all?