2D Collision
Momentum & CollisionsElastic collisions
Two objects colliding at angles in two dimensions with adjustable masses and velocities.
What to try
- Set both masses equal and approach angle to 0° — Ball 1 stops completely, transferring all its momentum to Ball 2.
- Set Ball 1 mass to 8 kg and Ball 2 to 1 kg — the heavy ball barely deflects while the light one shoots away.
- Slide the approach angle toward 75° — a glancing blow where both balls scatter nearly perpendicular to the collision line.
- Set Ball 2 speed equal to Ball 1 speed at 0° approach angle — the balls collide head-on and swap velocities symmetrically.
How this simulation works
Use the Ball 1 Mass and Ball 2 Mass sliders to set each object's weight. The Ball 1 Speed and Ball 2 Speed sliders set how fast each ball moves — Ball 2 begins stationary by default. The Approach Angle slider offsets Ball 2 sideways from Ball 1's path: at 0° the collision is head-on and all velocity transfers along one axis; at larger angles both balls deflect at two-dimensional angles, splitting into new trajectories. Press Start to launch, Pause to freeze mid-flight, and Reset to restore the initial configuration.