Electric Dipole

A dipole consists of two opposite charges of equal sizes at a relatively small distance. ![[Pasted image 20240306145019.png]]

• Characterized by a electric dipole moment $\vec p=q\vec d$ where $\vec d$ is the vector that goes from the negative to the positive charge.

• Why is it important? because it simplest model of an inhomogeneous charge distribution with zero net charge. At a long enough distance, any inhomogeneous charge distribution looks like a dipole.

#Potential Energy of an Electric Dipole

It’s not difficult to prove that the potential energy of a dipole in an electric field $\vec E$ is

• maximum when $\vec{p}$ is parallel to $\vec{E}$, minimum when it is perpendicular. As any mechanical system, the dipole will try to minimize the potential energy.