this power point is about electromagnetic induction. how magnetic field produces electric current

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2. GROUP MEMBERS ID NO
1. HERAN GETACHEW RU0131/13
2. KALKIDAN DEREJE RU0042/13
3. TINSAE KASSA RU3052/13
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3. CONTENT
-INTRODUCTION TO ELECTROMAGNETIC INDUCTION
-HISTORY OF ELECTROMAGNETIC INDUCTION
-FARADAY’S LAW OF INDUCTION
-LENZ’S LAW OF INDUCTION
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4. Introduction to electromagnetic induction
- Electromagnetic induction or induction is a process in which a conductor is put
in a particular position and magnetic field keeps varying or magnetic field is
stationary and a conductor is moving.
- This produces a voltage or EMF (electromotive force) across the electrical
conductor.
- It is described mathematically by Faraday’s law of induction
The induction of an EMF by a motion of a conductor across a magnetic field or
by a change in magnetic flux in a magnetic field is called Electromagnetic
Induction
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5. - Magnetic flux is a measurement of the total magnetic field which
passes through a given area
- It is a useful tool for helping describe the effect of magnetic force
on something occupying a given area.
Cont’d
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6. History of EMI
- In 1820, Oersted first discovered that a magnetic field is always
associated with an electric current.
- Electromagnetic induction was discovered by Michael Faraday in 1831 and James
Clerk Maxwell mathematically described it as Faraday’s law of induction.
- In 1831, August 29, Faraday discovered electromagnetic induction
by his famous induction ring experiment.
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7. Faraday’s law of EMI
FIRST LAW : whenever a conductor is placed in varying magnetic field, EMF
induce and this emf is called an induced EMF and if the conductor is a
closed circuit than the induced current flow through it.
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8. con’t
SECOND LAW: the magnitude of the induced EMF is equal to the rate of change of
flux linkage.
so, now the induced voltage is as follows;
e = N × dΦdt
where,
e is the induced voltage
N is the number of turns in the coil
Φ is the magnetic flux
t is the time
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10. LENZ’S LAW OF EMF
- Lenz law of electromagnetic induction states that, when an
emf induces according to Faraday’s law, the polarity (direction)
of that induced emf is such that it opposes the cause of its
production.
According to Lenz’s law
E = -N (dΦ/ dt) (volts)
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12. REFERENCE
 EXTREME PHYSICS BOOK
 https://www.toppr.com
https://www.techtarget.com
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13. THANK YOU
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