Potential of Line Charge

The potential of a line of charge can be found by superposing the point charge potentials of infinitesmal charge elements. It is an example of a continuous charge distribution.

Potential for Ring of Charge

The potential of a ring of charge can be found by superposing the point charge potentials of infinitesmal charge elements. It is an example of a continuous charge distribution. The ring potential can then be used as a charge element to calculate the potential of a charged disc.

Since the potential is a scalar quantity, and since each element of the ring is the same distance r from the point P, the potential is simply given by If the charge is characterized by an area density and the ring by an incremental width dR', then:

In this form it could be used as a charge element for the determining of the potential of a disc of charge.

Potential for Disc of Charge

The potential of a disc of charge can be found by superposing the point charge potentials of infinitesmal charge elements. It is an example of a continuous charge distribution. The evaluation of the potential can be facilitated by summing the potentials of charged rings. The integral over the charged disc takes the form: