91Ó°ÊÓ

Figure 24.24

Magnetic or electromagnetic induction is the process of producing an electromotive force across an electrical conductor in a shifting magnetic field. Michael Faraday discovered induction in\({\rm{1831}}\), which James Clerk Maxwell formally defined as Faraday's law of induction.

The electric field in diagram (b) is perpendicular to the wire's length, but in diagram (a), the field oscillates along the wire's length. As a result, in diagram (a), an alternating current is formed along the entire length of the wire, but in diagram (b), it is only created along the diameter. Furthermore, if a charge is not already in motion, the magnetic field has no effect on it, and if it is, the magnetic force acts perpendicular to the motion, so pointing it in the direction of the wire has no effect.

Therefore, diagram (a) will have the electromagnetic wave successfully including the current in a wire.