AP Physics Interactive

Crash Carts

Explore momentum, kinetic energy, and collision types by launching two carts into each other on a frictionless track.

Simulation

Canvas animation
Waiting for collision

Physics Results

Compare the system before and after the collision.

Elastic collision

Before collision

Cart A initial velocity+2.00 m/s
Cart B initial velocity-1.00 m/s
Total momentum1.00 kg·m/s
Total kinetic energy2.50 J

After collision

Cart A final velocity-1.00 m/s
Cart B final velocity+2.00 m/s
Total momentum1.00 kg·m/s
Total kinetic energy2.50 J

Momentum check

Conserved

Total momentum should stay constant.

Kinetic energy change

0.00 J

Should be conserved for elastic collisions.

Center of mass

vCM = 0.50 m/s

Constant if there is no external force.

Interpretation

In a perfectly elastic collision, both total momentum and total kinetic energy are conserved.