Hello, this is a question regarding planar physics. Suppose we have multiple bodies. We can ignore their individual shape and angular speed. So every body is represented by it's position, mass and moment of inertia about it's center of mass. Now my question is, how to calculate the moment of inertia, angular momentum and angular velocity of all of these bodies together about their common center of mass? I've got something going, but it's not working as expected. Thanks for your help!