1. The problem statement, all variables and given/known data For an assignment, I was shown a video where two identical pucks were launched at each other. They were not spinning when launched. They had Velcro on their edges so they stuck to each other when they collided. They hit off-center from each other. Due to conservation of angular momentum, when they collided, they stayed in place at the point of collision and just rotated. Then I was asked, if the mass of each puck was doubled, what would happen to the angular speed, ω. 2. Relevant equations ----eqn1--------- m(r^2)ω ----eqn2--------- m(r^2)ω + m(r^2)ω = (m(r^2) + m(r^2))ω 3. The attempt at a solution First, I tried using the simple equation for angular momentum: m(r^2)ω If the mass is doubled, then angular speed is halved. But then I saw another equation for conservation of momentum: m(r^2)ω + m(r^2)ω = (m(r^2) + m(r^2))ω With this equation, when mass is doubled, angular speed stays the same. Which one do I use? Or am I even going about this correctly?