ABSTRACT
Armed with Green’s function for the semi-infinite dielectric arrangement, we can now answer mechanical questions about interaction energy and force. The total energy of a charge distribution in the presence of the dielectric medium. The force on the dielectric body is now found as the negative of that acting on the charge e, as produced by the latter’s own Coulomb field (which force we know to be zero), and by the Coulomb field of the image charge. This derivation is in the spirit of the first such calculation, but lacks the reference to the energy.
