Faraday’s Law of electromagnetic induction

The phenomenon by which an emf is induced in a conductor when it is cut by magnetic flux is known as electromagnetic induction.

Faraday’s First Law

It states that,When ever a conductor cuts a magnetic field or viceversa an emf is induced in it and it setsup in such a direction so as to oppose the cause of it.

Faraday’s second law

It states that the magnitude of induced emf is equal to the rate of change of flux linkage.

Mathematically

e = -NdØ/dt

e – induced emf

N- number of turns of coil

dØ/dt – rate of change of flux

the minus sign represents that the induced emf or current sets up in a direction so as to oppose the cause of it.

Induced emf

Induced emf could be classified into dynamically induced emf and statically induced emf.

Dynamically induced emf

This is the emf induced due to the motion of a conductor in a magnetic field.

Mathematically

e = Blv volts

e-induced emf

B – flux density of magnetic field in Tesla

l = length of conductor in meters

v- velocity of conductor in m/s

if the conductor moves in an angle θ,the induced emf could be represented as

e= Blvsinθ

the direction of induced emf is given by f lemmings right hand rule.

Statically induced emf

The emf produced in a conductor due to the change in magnetic field is called statically induce emf .It could be classified into two

1)self induced emf and 2)mutual induced emf

Written by John on September 10th, 2008 with 1 comment.
Read more articles on Electrical Machines and Electromechanical energy conversion.

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