Low cost easy to use lab for studying elastic and inelastic collisions.

It includes a curved aluminum track with base for attaching to a table or bench with a C-clamp; a block of wood; and two rubber balls which are identical in appearance but differ greatly in the degree to which they bounce (Happy/Sad balls).

The 'Happy' ball, which bounces, is made of neoprene rubber. The 'Sad' ball, which does not bounce, is of polynorbornene rubber.