Rotating Disk with Erasers (1D55.30)

Description:

A horizontal rotating disc with a smooth surface. Chalk board erasers with various surfaces are placed on the disc, which is rotated slowly until the erasers slide off; how long this takes depends on rotation speed, distance from the center, and eraser surface. A weight attached to the rotation axis by a rubber band shows qualitatively how the centripetal force increases with rotation speed.