Who invented the Van de Graaff generator in 1929?

Robert J. Van de Graaff invented the Van de Graaff generator in 1929.

The machine uses a moving belt to transport electric charge to a large hollow metal dome. Because charge on a conductor spreads over its outer surface, the dome can reach an extremely high electric potential. The generator may produce very high voltage while supplying only a small current.

Van de Graaff developed the device while working as a physicist in the United States. It became important in early particle-accelerator research, where high voltages were used to accelerate charged particles into atomic nuclei. Later versions were also built for museum demonstrations and classroom experiments.

The generator is sometimes mistaken for an ordinary electrostatic machine such as a Wimshurst machine. Both create high voltages, but the Van de Graaff generator relies on a continuously moving belt and a spherical terminal.