Rotation of electric dipole in an E Field

     This physlet illustrates the motion of a electric dipole in an external electric field.
     We are seeing the dipole "from the side", so there is the straight piece (like an imaginary bar connecting them) and two "circles" on the end to indicate the charges. The charges are opposite each other, and we set the sign/magnitude of the left charge (when it starts) - the other will automatically be set. If the charge is positive, it is green, negative is red. The force vectors (from the electric field) are also shown.
     You can change the strength of the electric field, and the direction of the field (Positive E = UP, Negative E = DOWN). You can change the magnitude/sign of the left charge (other automatically set). You can also change the intial angle - this is the angle that the dipole moment (vector from the negative to the positive charge) makes with the electric field.

    Theta =  deg (angle of dipole, relative to field direction)
    Ey =  E (- = down, +=up)
    q (green=+ red=-) =  coulombs