⚽ Ball Bounce with Spin and Friction: Slip, Stick and Roll with Contact-Point Angular Momentum

A spinning ball hits a rough floor: a Coulomb-friction impulse model decides between slipping and sticking, changes the horizontal speed and spin, and conserves angular momentum about the contact point. Backspin zips the ball back, topspin kicks it on, and a live sweep plots outgoing speed against incoming spin.