 A tabletop version can produce on the order of 100,000 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.