Ping-pong Ball Capacitor

PIRA: 5B10.35

Two parallel metal plates are connected to the Van de Graaff generator so that they are charged oppositely. This is done by taping one end of a wire to the sphere of the generator and clipping the other end to the top (or bottom) plate, and grounding the bottom (or top plate) with another wire. With the generator turned on, metal-coated ping pong balls are tossed between the plates. The balls will pick up charge from one plate and then accelerate toward the other (oppositely charged) plate. The cycle will continue until the generator is turned off, at which point the ping pong balls will slowly transfer charge between the plates, bouncing several more times, until the plates are neutral.