Radiative properties of a moving electric dipole

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The electric and magnetic fields of an electric dipole in arbitrary motion, found in the preceding paper, are used to obtain radiative properties such as the rate of energy loss and the rate of momentum loss by the source to the electromagnetic field. These quantities, quadratic in the fields, are dependent on the fields at large distances from the source. These rates are calculated for three special cases. The first is a high–frequency oscillating dipole moving in a general trajectory where the rates of energy loss are found when the dipole is (a) perpendicular to the velocity, and (b) parallel to the velocity. The corresponding rates of momentum loss are in the direction of the velocity and are proportional to the rates of energy loss. The second case is that of a permanent dipole moving with non–uniform velocity in a straight line. The rate of energy loss is dependent on both the acceleration and the rate of change of acceleration. Though the momentum loss is in the direction of the velocity, as in the first case, its magnitude is not proportional to the rate of energy loss. Finally, the radiation from a permanent dipole moving in a circle at a fixed speed is discussed. The rates are large for small radius of the circle and/or speeds approaching the speed of light.