Collision Lab — Free Online Momentum & Collision Physics Game
Collision Lab teaches conservation of momentum, elastic and inelastic collisions, and Newton's cradle physics through 8 progressively complex collision puzzles. Each scenario uses real physics — the same equations taught in A-level and first-year university physics.
The physics behind the game
Conservation of momentum
Momentum is always conserved in collisions — regardless of elasticity. This is a consequence of Newton's third law: the force one ball exerts on the other is equal and opposite.
Elastic collision (e = 1)
Both momentum and kinetic energy are conserved. For equal masses: the first ball stops dead and the second moves with the original velocity. This is Newton's cradle in action.
Inelastic collision (e = 0)
Maximum kinetic energy is lost (converted to heat/sound). The balls stick together and move as one. The combined momentum equals the original momentum.
Coefficient of restitution
Real collisions fall between e=0 and e=1. A superball is ~0.9. A lump of clay is ~0. A billiard ball is ~0.95. The game shows all these regimes.