The applet has two modes, elastic, which is represented by a collision between a lightweight cannon projectile that sticks to a heavier cart and inelastic which is represented by the collision of two railroad carts on a frictionless track. Parameter tags control the masses and momentum of the objects."> The applet has two modes, elastic, which is represented by a collision between a lightweight cannon projectile that sticks to a heavier cart and inelastic which is represented by the collision of two railroad carts on a frictionless track. Parameter tags control the masses and momentum of the objects.">