when the magnetic flux linked to a conductor changes in any way, an electromotive force (emf) is induced in the conductor
magnetic flux
the number of magnetic field lines passing through a given closed surface
magnetic flux linkage
the product of the magnetic flux and the number of turns of a conductor
Faraday's laws
an induced emf will occur in any conductor linked with a changing magnetic flux
the magnitude of the induced emf is proportional to the rate of change of magnetic flux linkage
Lenz's law
the direction of the induced emf is such that its effect is to oppose the original magnetic flux change
alternating voltage
a time-dependent voltage, which varies between positive and negative values
alternating current
a time-dependent current, which varies between positive and negative values
transformer
an electromagnetic device that is able to change an alternating electrical supply from one potential difference to another; a step-up transformer produces a larger potential difference than it is supplied with, and a step-down transformer produces a smaller potential difference than it is supplied with
