A time-varying current flows through an inductor. The time-varying magnetic field excites an induced electric field and an induced electromotive force is generated in the coil winding. The supply potential blocks the induced electromotive force from generating conduction current. The time-varying induced electric field excites a magnetic field, forming an electromagnetic wave. A current-carrying conductor and the inductor are fixed together to form a system. The conductor is subjected to an Ampere force in the magnetic field of the electromagnetic wave. Electromagnetic wave is independent of the inductor and independent of the system. The Ampere force is an external force. It can drive the system. Like rocket engines, the system enables propulsion in space. It has the advantage of requiring only electrical power, not propellant.