Electromagnet class XII.docx

This is a Word document on electromagnet and it is for Class XII.
It also contains the certificate that can be filled by each individual separately and also has an acknowledgment. It also contains colored images for a better view.
Thank You :}

1. INDEX


 CERTIFICATE
 ACKNOWLEDGEMENT
 AIM OF PROJECT
 INTRODUCTION
 THEORY
 APPLICATIONS OF EMI
 OBSERVATION
 CONCLUSION
 PRECAUTIONS
 BIBLIOGRAPHY

2. CERTIFICATE

This is to certify that ___________________, a
student of class
_________________has successfully completed
the research on the topic “Study of the
Phenomenon of Electromagnetic Induction”,
under the guidance of
__________________(Subject Teacher) during the
year 2021-2022 in partial fulfillment of Physics
practical examination of Central Board of
Secondary Education (CBSE).

3. Principal.
Subject Teacher.
______________
________________

4. ACKNOWLEDGEMENT

I warmly acknowledge the continuous
encouragement and
timely suggestions offered by our dear
Principal
________________. I extend my hearty thanks for
giving
me the opportunity to make use of the
facilities available in
the campus to carry out the project
successfully.
I am highly indebted to _____________________
for the constant supervision, providing
necessary information and supporting

5. in completing the project. I would like to
express my
gratitude towards them for their kind
cooperation and
encouragement.

Finally, I extend my gratefulness to one and
all who are
directly or indirectly involved in the successful
completion of
this project work.

I am making this project not only for marks
but to also
increase my knowledge.

6. INTRODUCTION

Electro Magnet:
An electromagnet is a type of magnet in
which the magnetic field is produced by
electric current. The magnetic field
disappears when the current is turned off.

Induction:
This process of generating current in a
conductor by placing the conductor in a
changing magnetic field is called
induction.

Electromagnetic Induction:

7. Electromagnetic induction is the
production of a potential difference
(voltage) across a conductor when it is
exposed to a varying magnetic field.
Electromagnetic induction is when an
electromagnetic field causes molecules in
another object to flow. Induction can
produce electricity (in coils), heat (in
ferrous metals), or waves (in a radio
transmitter).
Finally, it refers to the phenomenon where
an emf is induced when the magnetic flux
linking a conductor changes.

8. Magnetic Flux:
Magnetic Flux is defined as the product of
the magnetic flux density and the area
normal to the field through which the
field is passing. It is a scalar quantity and
its S.l. unit is the weber (Wb).
Φ = BA

9. PRINCIPLE

Electromagnetic induction (or sometimes
just induction) is
a process where a conductor is placed in
a changing magnetic
field (or a conductor moving through a
stationary magnetic
field) causes the production Of a voltage
across the
conductor. This process of
electromagnetic induction, in
turn causes an electrical current it is said
to induce the
current.

11. THEORY

Invention:
Michael Faraday is generally credited with
the discovery o induction in 1831 though
it may have been anticipated by the work
of Francesco Zantedeschi in 1829. Around
1830 to 1832. Joseph Henry made a
similar discovery. but did not publish his
findings until later.

Induced e.m.f:
If magnetic flux through a coil is altered
then an E.m.f. will be

12. generated in the coil. This effect was first
observed and explained by Ampere and
Faraday between 1825 and 1831. Faraday
discovered that an e.m.f. could be
generated either by,
a) Moving the coil or the source of
flux relative to each other or by
b) Changing the magnitude of the
source of magnetic flux in some way.
Note the the e.m.f is only produced while
the flux is changing.

Lenz’s Law:

13. When an emf is generated by a change in
magnetic flux according to Faraday's Law,
the polarity of the induced emf is such
that it produces a current whose magnetic
field opposes the change which produces
it. The induced magnetic field inside any
loop of wire always acts to keep the
magnetic flux in the loop constant. In the
examples below, if the B field is

14. increasing. the induced field acts in
opposition to it.

15. APPLICATION OF
ELECTROMAGNETIC
INDUCTION

Electric Generator:
The EMF generated by Faraday's law of
induction due to relative movement of a
circuit and a magnetic field is the
phenomenon underlying electrical
generators. When a permanent magnet is
moved relative to a conductor, or
vice versa. an electromotive force is
created. If the wire is connected through
an electrical load. current will flow. and
thus electrical energy is generated,

16. converting the mechanical energy of
motion to electrical energy.


Electric Transformer:

17. The EMF predicted by Faraday's law is
also responsible for electrical
transformers. When the electric current in
a loop of wire changes. The changing
current creates a changing magnetic field.
The second wire in reach of this magnetic
field will experience this change in the
magnetic field as a change in its coupled

18. magnetic flux, therefore. an electromotive
force is set up in the second loop called
the induced EMF or transformer EMF. If
the two ends of this loop are connected
through an electrical load, current will
flow.

19. Faraday’s Experiment:
 One the scientists Faraday performed
series of experiments and based on the
results he gave the law on induction.
 He introduced the phenomenon of
electromagnetic induction.
 Induction means to induce or to generate
something.
 Electromagnetic Induction means the
production of electric
current due to the magnetic field.
 Magnetic field is capable of producing
current in a conductor
 Faraday took a coil and attached a
galvanometer to it.

20.  As there is no battery attached therefore
there is no source of current.
 He brought the magnet near the coil.
 When the magnet is moved towards the
coil galvanometer showed deflection.
 Galvanometer even showed the deflection
in the opposite
direction When the magnet is taken away
from the coil.
 When the magnet was not moved there
was no deflection in the galvanometer.
 This shows current is related to a magnet.
 Faster the magnet is moved the more is
thc deflection in the galvanometer. This
showed more and more current flows if
the magnet is moved very fast.

21.  Same effect was observed if the coil is
moved and the magnet was not moved.

22. EXPERIMENT


Aim:
To study the phenomenon of electromagnetic
induction.

Materials Required:
Magnetic bar, a galvanometer, coil and
connecting wires.

Procedure:
1. Take a coil of wire having a large number
of turns.

23. 2. Connect the end of the coil to a
galvanometer.
3. Take a strong bar magnet and move its
north pole into the coil
and observe the changes in the galvanometer
needle.
4. Repeat earlier step with the south pole of
the bar magnet.
5. Now repeat the procedure with the coil
having a different number of turns and the
variation in the deflection of the
galvanometer needle.

24. Observations:
l. When we move the magnet in or out of the
coil, the needle Of
galvanometer gets deflected in different
directions.
2. When we insert the north pole (N) Of bar
magnet into the coil,
the deflection is towards right.
3. When we insert the south pole (S) of bar
magnet into the coil, the
deflection is towards left.
4. When we move the bar magnet in or out
of the coil with varying

25. speed, the speed of deflection changes
accordingly.
5. As we increase the number of turns in the
coil, the deflection
increases.
6. Relative motion between magnet and coil
induced electric current in the coil.

26. DIAGRAMS

28. RESULT
I. The deflection of galvanometer needle
indicates the presence of
current in the coil.
2. The direction of deflection gives the
direction of flow of current.
3. The speed Of deflection gives the rate at
which the current is
induced.
4. The deflection in galvanometer Changes
with the Change in
number of turns in the coil - more the
number of turns in the coil
greater is the deflection.

29. CONCLUSION

From this experiment, Faraday concluded that
whenever there is
relative motion between a conductor and a
magnetic field, thc flux
linkage with a coil changes and this change in
flux induces a voltage
across a coil.

30. BIBLIOGRAPHY
 Physics NCERT Book class XII
 www.Wikipedia.com
 Google Images
 Slideshare.com






THANK

31. YOU