1. The problem statement, all variables and given/known data Two people of different masses are riding in a sleigh on frictionless ice. One has mass m1 and the other has mass m2. When they jump out of the sleigh each has speed u respect to the sleigh. (I). What is the final velocity of the sleigh if they jump simultaneoulsy in the +x direction? (II). What is the final velocity of the sleigh if one with mass m1 jumps first and the other person with mass m2 jumps a few seconds later? 2. Relevant equations conservation of momentum and energy (I think) 3. The attempt at a solution I tried using momentum and energy but somehow I ended up having u = 0, which seems to be wrong. Please help!