Equation of Motion of an Electric Charge

Abstract

The appearance of the time derivative of the acceleration in the equation of motion (EOM) of an electric charge is studied. It is shown that when an electric charge is accelerated, a stress force exists in the curved electric field of the accelerated charge, and this force is proportional to the acceleration. This stress force acts as a reaction force which is responsible for the creation of the radiation (instead of the "radiation reaction force" that actually does not exist at low velocities). Thus the initial acceleration should be supplied as an initial condition for the solution of the EOM of an electric charge. It is also shown that in certain cases, like periodic motions of an electric charge, the term that includes the time derivative of the acceleration, represents the stress reaction force.