This Demonstration considers the behavior of electric dipoles in an electric field produced by a pair of infinite parallel plates.
Use the "" slider to set the charge density. Select "single dipole" and use the slider "" to set the charge of the dipole and the slider "" to set the distance separating the charges of the dipole. The angle is chosen randomly. The left-hand panel shows a plot of the potential energy of the dipole, with the red dot indicating the specific value for the given parameters. The right-hand panel shows the plates that produce the electric field and the values of the charge density. Use the sliders to vary the electric field and the charge density of the plates, the potential energy stored in the dipole. The legend shows the torque produced by the electric field on the dipole and the angle between the dipole and the field.
With "many dipoles" you can show the dipoles either as arrows or charge using the "show dipoles as arrows" checkbox.