Van de Graaff generator science definition
A type of electrostatic generator used to build up static electrical charge of very high voltages by transferring electric charge from a power supply to a spherical metal terminal. A high-voltage source transfers charge to a nonconducting conveyor belt, usually made of silk or rubber, which continuously redeposits the charge on the insulated metal terminal, where it accumulates. Even small Van de Graaff generators can accumulate a static charge of 100,000 volts; the largest, up to 10 million volts.

Van de Graaff generator
Positive charge is transferred by a metal brush to a rotating belt, which carries the charge up to the spherical electrode where it accumulates.
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