Electromagnetic induction refers to generating an electric current by moving a conductor through a magnetic field or changing the magnetic field around the conductor. Michael Faraday discovered electromagnetic induction in 1831 through experiments with coils and magnets. Electromagnetic induction underlies technologies like electric generators and transformers. It is explained by Faraday's law, which states that the induced voltage is proportional to the rate of change of the magnetic flux through the circuit.

1. ELECTROMAGNETIC INDUCTION

2. WHAT IS
ELECTROMAGNETIC
INDUCTION ?
❖ Electromagnetic induction refers to the generation of an electric
current by passing a metal wire through a magnetic field.
❖ Electromagnetic or magnetic induction is the production of an
electromotive force
across an electricalconductor in a changing magnetic field.
❖ When an induced current is produced because of voltage
production (E.M.F) due to a changing magnetic field, it is called
electromagnetic induction.

3. CHARACTERISTICS OF
ELECTROMAGNETIC INDUCTION
❖ For movements between magnetic bar and the conductor,there will
be deflectionsin galvanometer.
❖ If the bar and the conductor remain steady then there will be no
deflections in the galvanometer.
❖ If the pole of the magnetic bar is changed,the direction of induced
current will change
❖ When the loops in the coil increasesthe deflection become greater
and when loops decreases the deflection become smaller.

4. HISTORY OF
ELECTROMAGNETIC
INDUCTION
In 1820, Oersted first discovered that a
magnetic field is Always associated with an
electric current.
In 1831, August 29, Faraday discovered
electromagnetic induction by his famous
induction ring experiment.

5. ELECTROMAGNETIC INDUCTION TEST
Make a connection between the galvanometer and the copper coil with
the electric wires.
Try to push the bar inside of the coil.
Take away the bar from the from the coil.

6. LAWS OF
ELECTROMAGNETIC
INDUCTION
Faraday's Law : It states that, the E.M.F
induced in a wire is proportional to
the rate of the flux through the loop.
Neumann's Law : The magnitude of
the induced E.M.F is proportional to
the rate of change of the magnetic
flux linking the circuit.
Len's Law : The induced E.M.F acts to
the circulatea current in a direction
that oppose the change in flux which
caused the induced E.M.F

7. TRANSFORMERS
- A transformer is an electrical device which,by the
principlesof electromagnetic induction.
- It transfers electrical energy from one electric circuit to
another,without changingthe frequency.
- Transformerseither increases or decreases AC voltage, two
types step-up and step-down.

8. ELECTRICAL
GENERATOR
❖ Generator,operateson the principle of
electromagneticinduction.
❖ A generator is a device that convertsmotive power
into electrical power for use in an external circuit.
❖ In the simplest form of generator the conductor is
an open coil of wire rotating between the poles of a
permanent magnet.

9. QUIZ
1. The direction of the induced field can be predicted by____
Kepler’s law
Newton’s law
Lenz’s law
Faraday’s law

10. 2. Fill in the blanks: Electric
generator convertselectrical
energyinto____
1.Chemicalenergy
2.Thermalenergy
3.Electricalenergy
4.Solar energy

11. 3. The phenomenon called electromagnetic
induction was first investigated by
Newton
Kepler
Faraday
Galileo

12. 4. Lenz’s law is derived from ____.
Kepler’s law
Newton’s law
Coulomb’s Law
Faraday’s law

13. 5. Factors that affect the voltage
generation in Faraday’s experiment is
Number of Coils
Changing Magnetic Field
Changing Environment
Option a) and b)