Rattleback Reverses Direction

In one direction it wobbles, stops, and reverses. Ask students to predict what will happen. Spin it one way, then the other. Key idea: Its asymmetric shape couples rocking and spinning; friction transfers energy between motions. Ask: Why does it only like one spinning direction? Safety and cleanup: Use on a tray away from edges. https://www.physics.colostate.edu/physics-demos/rattleback/