Van de Graaff Generator

DOE-HDBK-1108-97

Radiological Training for Accelerator Facilities

Instructor's Guide

Lesson Plan

Instructor's Notes

Acceleration

The acceleration of the electron by this

electrical force also increases the energy of the

electron.

Electron volt

The amount of acceleration is determined by

the potential difference measured in volts (V)

in this electrical field.

One electron volt (eV) is the energy gained by

an electron accelerated through an electric

potential of one volt.

An electron accelerated across a gap by means

of a 10,000 volt, or 10 kilovolt (kV), potential

difference is said to have gained 10,000

electron volts (10 keV) of energy after

crossing the gap.

Van de Graaff Generator

One of the first machines to produce laboratory-

accelerated particles was the Van de Graaff generator.

Operation

The Van de Graaff consists of a polished metal

sphere and a moveable belt. The function of

the belt is to carry an electrical charge up to the

sphere where it is stored. This process can be

continued until a very high potential is

developed in the sphere.