Electrical Engineering ⇒ Topic : Induced E.M.F.

Induced E.M.F.

When the magnetic flux linking a conductor (or coil) changes, an e.m.f. is induced in it. This change in flux linkages can be brought about in the following two ways :

• The conductor is moved in a stationary magnetic field in such a way that the flux linking it changes in magnitude. The e.m.f. induced in this way is called dynamically induced e.m.f. (as in a d.c. generator). It is so called because e.m.f. is induced in the conductor which is in motion.
• The conductor is stationary and the magnetic field is moving or changing. The e.m.f. induced in this way is called statically induced e.m.f. (as in a transformer). It is so called because the e.m.f. is induced in a conductor which is stationary.

It may be noted that in either case, the magnitude of induced e.mf is given by dΦ/dt or derivable from this relation.