Most people have seen a Van de Graaff generator before at a science centre or on TV. You know that it makes peoples' hair stand on end, but do you actually know how it works? A Van de Graaff generator pulls electrons from the Earth, moves them along a belt and stores them on the large sphere.
How the Generator Works
A Van de Graaff generator is an electrostatic generator which uses a moving belt to accumulate electric charge on a hollow metal globe on the top of an insulated column, creating very high electric potentials. It produces very high voltage direct current DC electricity at low current levels. It was invented by American physicist Robert J. Van de Graaff in A tabletop version can produce on the order of , volts and can store enough energy to produce a visible spark. Small Van de Graaff machines are produced for entertainment, and for physics education to teach electrostatics ; larger ones are displayed in some science museums. The Van de Graaff generator was developed as a particle accelerator for physics research; its high potential is used to accelerate subatomic particles to great speeds in an evacuated tube.
Van de Graaff generator - the basics
The Demonstration: The volunteer puts her hand on the metal ball and her hair stands on end. Quick Physics: The Van de Graaff generator works by static electricity, like shuffling your feet across the carpet and shocking yourself on the doorknob. The electrons move up the rubber band to the metal ball and into the person. The electrons repel each other, so they try to get as far away from each other as possible.
Invented around , the Van de Graaff generator is a popular tool for teaching the principles of electrostatics. Others just call it "that thing that makes your hair stand on end. American physicist Robert J. Van de Graaff began developing the high-voltage electrostatic generator that bears his name around They started out relatively small and got much bigger; one made in measured 40 feet high and could generate 5 million volts!