A motor driven rubber belt delivers POSITIVE charge to the upper sphere. The lack of electrical field inside the metal sphere allows the charge to be conducted to the outside of the sphere and to develope high potentials.
Many demontrations can be done using the Van de Graaff. Some suggestions:
Student hair raising.
Point discharge (coronal).
Electric Fields (use dipole probe)
Charging by induction.
Packing peanut fountain.
Ionization.
Volta's hail storm.
Franklin's bells.
Questions:
Would this work on the moon? (ie. with lower gravity and in a vacuum?)
