A variation on the traditional “Monkey and Hunter” experiment. Two balls are set up on an inclined incline. The first ball is given an initial velocity pointing in the direction of a second ball before it reaches the plane; the second ball is set free the moment that first ball reaches the incline. Since both balls are subject to gravity for the same amount of time before reaching one another, they still collide.
Be sure only to release the second ball (from rest) when the first ball has finished rolling off the ruler and has reached the incline; otherwise balls will not collide.
Location: Ruler L4-2, Plexiglass Ramp wall A, Balls DE-8