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# Faraday's law's of Electromagnetic induction

In 1831, Micheal Faraday formulated two laws on the bases of experiments. These laws are called Faraday's laws of electromagnetic induction.

## FIRST LAW

First Law of Faraday's Electromagnetic Induction state that whenever a conductor are placed in a varying magnetic field emf are induced which is called induced emf, if the conductor circuit are closed current are also induced which is called induced current.

Or

Whenever a conductor is rotated in magnetic field emf is induced which are induced emf.

## SECOND LAW

Second Law of Faraday's Electromagnetic Induction state that the induced emf is equal to the rate of change of flux linkages (flux linkages is the product of turns, n of the coil and the flux associated with it).

## FARADAY'S LAW'S EXPLANATION

**Let**

Initial flux linkages = Nφ1

Final flux linkages = Nφ2

Change in flux linkages= Nφ2 – Nφ1

=N((φ2-φ1)

If (φ2-φ1)= φ

Then change in flux linkages=Nφ

Rate of change of flux linkages= Nφ/t wb/sec

Taking derivative of right hand side we get

Rate of change of flux linkages= Ndφ/dt wb/sec

Rut according to Faraday's laws of electromagnetic induction, the rate of change of flux linkages equal to the induced emf, hence we can write

= Ndφ/dt volt

Generally Faraday's laws is written as

e = -Ndφ/dt volt

Where negative sign represents the direction of the induced current in the conductor will be such that the magnetic field produced by it will oppose the verb cause produce it.