Radial motion of highly conducting sphere in magnetic field

Radial motion of a highly conducting sphere in external magnetic field is c onsidered. It both perturbs the external magnetic field and generates an el ectric field. Exact analytic solution has been obtained previously for a un iformly expanding sphere. In the present paper a new exact solution is deri ved which is valid not only for expansion but for contraction as well. It a llows us to calculate analytically the total electromagnetic energy irradia ted by the sphere involved in periodical radial motion with arbitrary veloc ity. (C) 2000 American Institute of Physics. [S0022- 2488(00)04805-2].