Electric Charge comes in two kinds:

The electric force between two charges Q and q is given by Coulomb's Law,


We can describe the electric force as the result of an electric field,

F = E q

The electric field E due to a point charge Q is given by

An electric field originates on a positive charge.

Likewise, an electric field terminates on a negative charge.

The E-field inside a conductor is zero.

The electric potential energy of two point charges Q and q is given by

Potential energy is a scalar, so the PE due to more than a single electric charge is


El PE Due to Multiple Charges: An Example


Return to Ch 17, Electrostatics & Electric Energy
(c) Doug Davis, 2002; all rights reserved