Electricity

Van de Graaff with Aluminum Plates

Shows that 'like' charges repel. Use double sided tape to fasten an aluminum foil pie plate to the top of a Van de Graaff generator. Then stack a dozen more foil plates on top of the first one. When the Van de Graaff is turned on the plates float off one at a time, except of course for the taped on one.

Van de Graaff with Person and Plume

In this classic demonstration a person is insulated from the ground by standing on a board supported by four dryGirl with Van de Graaff drinking glasses, then charged up to many thousand volts. This demonstration is best done with caution. We've been told that metal in shoes and under the floor, can cause discharge and an alarming, though not dangerous, shock. Make sure the person is not using a pacemaker. This demostration works best with long, straight, fine hair. Their hair will stand on end if clean and dry. This again shows that like charges repel, but it also shows that voltage and energy are not the same, and that a complete circuit is needed for a sustained current.

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