The geometry of the system has a strong effect on the electric potential. Several geometries are discussed below.
- 2.2A: Point Charge
- Let us arbitrarily assign the value zero to the potential at an infinite distance from a point charge Q. “The” potential at a distance r from this charge is then the work required to move a unit positive charge from infinity to a distance r.
- 2.2B: Spherical Charge Distributions
- Outside any spherically-symmetric charge distribution, the field is the same as if all the charge were concentrated at a point in the center, and so, then, is the potential.