You have a pair of 'identical' rubber balls. Drop one ball and watch it bounce, just the way we know it should. Now drop the other and. . . it fails to bounce normally! These small, black rubber balls look and feel identical - except one bounces, the other doesn't. Use to illustrate elastic and inelastic collisions, and to introduce the coefficient of restitution. An eye-catching demonstration!
Dimensions: The ball diameter is about 1 inch.