The structure: a metal sphere is mounted on an insulating pillar. The pillar is fixed on a metal base. This apparatus can be used to do following electrostatics experiments:

 

1.       To demonstrate that when the electric charges of a conductor are in the equilibrium state, the electric charges distribute on the outer surface of the conductor only.

2.       To be used to do the experiment by which the concept of the capacitance of conductor may be summed up.

3.       Cooperated with other apparatuses, it can be used to do the experiments of electrostatic induction, electrostatic screening and so on.