  We calculate the self-force of a constantly accelerating electric dipole,
showing, in particular, that classical electromagnetism does not predict that
an electric dipole could self-accelerate, nor could it levitate in a
gravitational field. We also resolve a paradox concerning the inertial mass of
a longitudinally accelerating dipole, showing that the combined system of
dipole plus field can be assigned a well-defined energy-momentum four-vector,
so that the Principle of Relativity is satisfied. We then present some general
features of electromagnetic phenomena in a gravitational field described by the
Rindler metric, showing in particular that an observer fixed in a gravitational
field described by the Rindler metric will find any charged object supported in
the gravitational field to possess an electromagnetic self-force equal to that
observed by an inertial observer relative to which the body undergoes rigid
hyperbolic motion. It follows that the Principle of Equivalence is satisfied by
these systems.
