1. The problem statement, all variables and given/known data Two skaters, one mass 65kg and one mass 40kg, stand on an ice rink holding a pole of length 10m and negligible mass. Starting from ends of the pole, the skaters pull themselves along the pole until they meet. How far does the 40kg skater move? 2. Relevant equations 3. The attempt at a solution I don't even know what aspect of physics this is supposed to be about. EDIT: I looked at the solution and it says both skaters end up at the center of mass of the system. With that, the problem is trivial. But to better my understanding, why do both skaters end up at the COM?