ELEC2300

Electric Dipoles

Elementary Definition


Point particles with electric charge are referred to as point charges. Two point charges, one with charge and the other one with charge separated by a distance , constitute with an electric dipole. For this case, the electric dipole moment has a magnitude

and is directed from the negative charge to the positive one.

A stronger mathematical definition is to use vector, since a quantity with magnitude and direction, like the dipole moment of two point charges, can be expressed in vector form

where if the displacement vector pointing from the negative charge to the positive charge. The electric dipole moment vector also points from the negative charge to the positive charge.