Static charges lie only on an outside surface, and this
is the device that shows it.
Charge the sphere by touching it to the dome of a generator.
When a proof plane is touched to the outer surface, a charge will be acquired, but
when it is touched to the inside surface, no charge will be transferred.
sphere's re-entrant hole is 4 cm.
The sphere is 10 cm in diameter, and the device
height is 26 cm.
Recommended for use with our 25470 Adjustable Speed Van
de Graaff Generator.