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How to Get Metal to Repel a Charge

Metals such as copper and aluminum conduct electricity because the electrons in their atoms are loosely bound. A small amount of energy sets them in motion, producing an electric current. Metals accumulate static electricity for the same reason. Because opposite charges attract and like ones repel, putting a static electric charge on metal will cause it to repel objects with the same charge. A Van de Graff generator produces a large positive charge on its metal top. A pan of Styrofoam packing peanuts placed on the metal top will get some of the charge, and the peanuts will fly off.

Things You'll Need

Van de Graaff generator
Aluminum pie pan
Masking tape
Styrofoam peanuts
Metal discharge wand

Instructions

- 1
  Set the Van de Graaff generator on a sturdy, non-conducting surface, such as a wood or plastic table. Plug it into a standard AC socket but leave the generator off for now. Connect the metal discharge wand to the electrical ground on the Van de Graaff.
- 2
  Secure an aluminum pie pan to the aluminum dome of the Van de Graaff with a few pieces of masking tape. Fill the pan with Styrofoam peanuts.
- 3
  Turn the motor of the Van de Graaf generator on. Positive electric charges will accumulate in the aluminum dome, through the pan and into the peanuts. After a few seconds, the repulsive force between the metal and the peanuts causes them to levitate off the pan.
- 4
  Turn the Van de Graaff's motor off. Hold the discharge wand by the insulated handle. Touch the metal end to the Van de Graff's metal top. You should see a spark as the Van de Graaff safely discharges its static electricity.

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