Hey everyone! I am having some trouble with this problem. I would appreciate any help/advice/hints. A child of mass 33 kg jumps off of a wagon. After jumping, the child's velocity is 4.0 m/s . If the mass of the wagon is 7.2 kg, determine the velocity of the wagon after the child jumps off. All I have figured is that the childs momentum is 132 Kgm/s right. I am confused as to how to get the velocity of the wagon now. I do not have enough info to use Momentum= Mass X Velocity. Any help would be appreciated.