This document discusses electromagnetic induction and magnetic circuits. It explains Faraday's two laws of electromagnetic induction: 1) an electromotive force (emf) is induced in a conductor whenever the magnetic flux through the conductor changes, and 2) the magnitude of the induced emf is proportional to the rate of change of flux. It also describes Fleming's right-hand rule for determining the direction of induced emf and Lenz's law, which states that an induced current will flow in the direction that opposes the change producing it.

1. Magnetic
circuit
By
G R chaure

2. Electromagnetic induction :
The phenomenon of voltage induction in
conductor which is placed in magnetic field
First observed by Michel faraday
1) Faradays first law
2) Faradays second law
Magnetic circuit

3.  Faradays first law :
 Whenever magnetic line of force linking with
coil or conductor changes an emf is induced
in coil
 Such emf is present as long as this change is
taking place
 Faraday's law's of Electromagnetic
induction.gif
Magnetic circuit

4.  Faradays second law
 Whenever conductor cuts or is cut by
magnetic flux an emf is induced in conductor
 The magnitude of which is propositional to
The rate at which conductor is cut by magnetic
field
The magnitude of the induced emf is directly
propositional the rate change of flux linkage
Where flux linkage = flux * No of turns of coil
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5.  The expression for induced emf
e=N
𝑑Ø
𝑑𝑡
Where dØ represent change in flux
corresponding change in time
Thus
𝑑Ø
𝑑𝑡
represent the rate of change of flux
Direction of induced emf
1 Flemings right hand rule
2 Lenz's law
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6. Flemings right hand rule
 The three finger of right hand first finger second finger
and thumb outstretched in such way that they are
mutually perpendicular to each other then thumb point
in the direction of conductor motion first finger pointed
in the direction of magnetic field second finger indicates
the direction of induced emf
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7. Lenz’s law
 The direction of induced emf produced due to
the process of electromagnetic induction is
always such that
 It will set up a current to appose the basic
cause behind production
 E= -N
𝑑Ø
𝑑𝑡
 Where – N indicate that induced emf oppose
the cause producing it
Magnetic circuit