Description:
When a moving conductor shaped like a rod or wire interacts with a static external magnetic field, two effects conventionally associated with the direct action of magnetic forces arise. The first is an induced emf which in typical textbook accounts is initiated and maintained by a force proportional to the velocity of the conductor. The second is a resistive force, proportional to the induced current, presumed to act on the conduction electrons. We present an alternate theory to explain both effects that relies on an electric field within the conductor that has both transverse and axial components. The transverse field is analogous to the electric field associated with the Hall effect. The Hall fieldacts to transfer energy to the electrons, which generates the emf, and impede the motion of the ions, which is the origin of the resistive force. The combination of the axial field and the magnetic field is shown to act like a velocity selector. This clarifies the role of the magnetic field and avoids confusion about the energy transfer process (i.e. that magnetic forces can do mechanical work).