It is well known that whenever an electric current flows through a conductor, a magnetic field is generated around the conductor. And the converse of this is also true i.e. when a magnetic field around a conductor moves relative to the conductor, it produce a flow of electrons in the conductor. This phenomenon whereby an emf and hence current is induce in any conductor is cut by a magnetic flux is known as electromagnetic induction.

**Faradays First Law:**

*“Whenever the magnetic flux passing through a circuit or a conductor changes, an emf is induced in the circuit or conductor”*

In other words, whenever a conductor cuts the magnetic flux, an emf is induced in that conductor.

**Faradays Second Law:**

*“The magnitude of induced emf is equal to the rate of change of magnetic flux linkage.”*

Let us consider the magnetic flux of a coil having N turns changes from its initial value Ф

_{1}webers to a final value Ф_{2}webers in t seconds. Then, remembering that by flux-linkage meant the product of number of turns by the flux linked with the coil, we have:
Initial flux linkages = N Ф

_{1}and final flux linkage = NФ_{2}
Putting the above expression in the differential form, we get:

Usually, a minus sign is given to the right-hand side of expression to signify the fact that the induced emf set up current in such a direction that magnitic field produce by it oppose the very cause producing it (Lenz’s Law).

Lenz’s law states that

*“the direction of induced emf or current is such that it oppose the very cause producing it.”*