Michael Faraday (B. 22 September 1791 D. 25 August 1867) Photo Credit - |

#### Laws of Electromagnetic Induction

Any change in the magnetic field of a coil of wire will cause a voltage(emf) to be induced in the coil. No matter how the change is produced, the voltage will be generated. The change could be produced by changing the magnetic field strength by moving a magnet toward or away from the coil, rotating the coil relative to the magnet. The expression for emf induced is as follows,

where e = generated emf

N = number of turns of coil

Φ = flux

Above equation can be mathematically proved as below.

Suppose a coil has N number of turns and the flux through it changes from an initial value of Φ

_{1}Webers to final value Φ_{2}Webers in time "t" seconds.
Initial flux linkages = NΦ

_{1}
Final flux linkages = NΦ

_{2}
Therefore,

Negative sign signify the fact that the induced emf sets up current in such a direction that the magnetic effect produced by it opposes the very cause of producing it. The induced emf in the coil is equal to the negative rate of change of magnetic flux times the number of turns in the coil. It involves interaction of charge with magnetic field.

**First Law:-**Whenever a conductor is placed in a varying magnetic field and emf gets induced across the conductor and if the conductor is closed circuit then induced current flows through it.

**Second Law:-**It states that, "the emf induced is equal to the rate of change of flux linkages with the coil.

**Note:-**

- The flux linkages is the product of number of turns and the flux associated with the coil.
- The direction of induced emf is given by Fleming's Right Hand and Left Hand rule,

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