Robert Jemison Van de Graaff

Robert Jemison Van de Graaff (December 20, 1901 – January 16, 1967) was an American physicist and engineer born in Tuscaloosa, Alabama. He invented the electrostatic high-voltage generator that bears his name, which became a standard source of high energy for early nuclear physics, medicine and industry. By the time he died, more than 500 Van de Graaff accelerators were operating in over 30 countries.[1][2]

Early life and education

Van de Graaff was born at the Jemison–Van de Graaff Mansion in Tuscaloosa, the youngest of four sons of Adrian Sebastian Van de Graaff and Minnie Cherokee Jemison. A high school football injury in fall 1917 broke his femur and injured his back, and he never graduated from high school. He nonetheless enrolled at the University of Alabama in 1918 and earned a bachelor’s degree in 1922 and a master’s degree in 1923, both in mechanical engineering.[2][1]

The Van de Graaff generator

In September 1929 Van de Graaff joined Princeton University as a National Research Fellow. That fall he built a proof-of-concept machine that produced about 80,000 volts, limited by corona discharge from its metal can. By November 1931 his demonstration model produced more than 1.5 million volts, over twice the highest direct-current voltage previously achieved.[2] Different sources give slightly different figures for the early models, and the Encyclopedia of Alabama reports a demonstration of more than one million volts in 1934.[1]

Applications

Van de Graaff and his collaborator John G. Trump built a medical X-ray generator in 1937 at Harvard’s Huntington Memorial Hospital, the first electrostatic accelerator used in clinical medicine. During World War II he directed the High Voltage Radiographic Project at MIT, which built X-ray generators for inspecting U.S. Navy ordnance.[2][1] In late 1946 he, Trump and Denis Robinson co-founded High Voltage Engineering Corporation, the first company formed to manufacture particle accelerators. In the 1950s he promoted tandem accelerators and, in the late 1950s, invented the insulating core transformer.[2]

Honors and death

His honors include the Elliott Cresson Medal of the Franklin Institute (1936), the Duddell Medal of the Institute of Physics (1947) and the American Physical Society’s Tom W. Bonner Prize (1966).[2] He left MIT in 1960 to become full-time chief scientist at High Voltage Engineering. Van de Graaff died on January 16, 1967, after a heart attack at his home in Lexington, Massachusetts.[2] The Van de Graaff generator is still used in physics classrooms and science museums worldwide, and his Round Hill machine is displayed at the Museum of Science in Boston.

FAQs

Where was Robert Van de Graaff born? In Tuscaloosa, Alabama, on December 20, 1901.

What is a Van de Graaff generator used for? It produces very high voltages and was used to accelerate particles for nuclear research, to make X-rays for medicine and industry, and in science demonstrations.

Sources

1. Encyclopedia of Alabama: Robert Van de Graaff
2. Wikipedia: Robert J. Van de Graaff

Editorially reviewed by Specialty Digest Editorial TeamLast reviewed November 10, 2026Researched and drafted with AI assistanceReport an issue