# Collision Modeling Activities

Install Ejs and then right-click on a launch node (green arrow) to copy the Free Fall model from this package into the Ejs workspace to do the following activities.

### Head on collision

Set the impact parameter to zero and observe what happens in a head on collision between two equal masses? Explain why the observed motion conserves both energy and momentum in a trivial manner.

### Vector nature of momentum.

Why are the vertical velocity components of the two balls always equal but opposite if the particles have equal mass? What impact parameter that produces a 90 degree angle between the balls after collision?

### Unequal Mass

Extend the model to simulate the collision of two unequal masses of equal size. Predict the result of a head on collision if the stationary mass m2 is much larger than the incident mass m1. Repeat for a stationary mass m2 that is much smaller than the incident mass m1.

### Inelastic Collision

Change the model to simulate the collision of two particles that stick together. Such a collision is said to be totally inelastic because the maximum about of kinetic energy is converted to heat.