Static Electricity: Point Discharge

Charge Distribution on a Conductor All static charges reside on the outside of a conductor (because the charges will be of the same type, and will try to get as far as possible from each other) Static charge tends to accumulate where the conductor is most pointed

Point Discharge At a very sharp point there is a large accumulation of charge This creates a very strong electric force field in the region around this point Ions in the air are either strongly attracted or strongly repelled from the tip of a charged conductor  Can be demonstrated using a Van de Graaff generator Lightning conductors are based on this phenomenon

Van de Graaff generator Instrument used to demonstrate electrostatic effects Smooth dome is insulated from earth by tall support pillars Rubber belt moves on a motor-driven pulley Two metal combs - one at the lower pulley connected to earth and one at the upper pulley connected to the dome

The voltage (amount of static charge) of the generator depends on the size of the dome and the quality of the insulating pillars All of the charge resides on the outside of the dome

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