This apparatus helps you visualize "time" in the oscillations of a rolling ball. Study uniformly accelerated motion by rolling a ball down a curved track. The ball will oscillate back and forth, leaving a trail in powder you have supplied. Measure the distances traveled between each half wavelength and subtract from the one following to demonstrate that the differences are constant. The fact that a ball is rolling down the incline, not a sliding block, changes the mathematical workup performed in most physics labs today. Includes: curved plastic track; wood support at one end; 3/4" diameter steel ball; instructions with theory. You need lycopodium or other fine powder.