Its a simple project for class 12th science students. This project is collected from various sources including Google, Wikipedia and Slideshare, Youtube and many more.
2. NAME OF THE SCHOOL
DEPARTMENT OF PHYSICS
CERTIFICATE
This is to certify that NAME OF THE STUDENT, a
student of class XII has successfully completed the
research on the below mentioned project under the
guidance of ( Subject Teacher ) during the year 2014-15
in partial fulfillment of physics practical examination
conducted by AISSCE, New Delhi.
Signature of external examiner Signature
of Physics Teacher
3. ACKNOWLEDGEMENT
In the accomplishment of this project successfully,
many people have best owned upon me their
blessings and the heart pledged support, this time I
am utilizing to thank all the people who have been
concerned with project.
Primarily I would thank god for being able to complete
this project with success. Then I would like to thank
my principal (NAME OF THE PRINICIPAL) and
physics teacher (NAME OF THE PHYSICS TEACHER),
whose valuable guidance has been the ones that
helped me patch this project and make it full proof
success. His suggestions and his instructions have
served as the major contributor towards the
completion of the project.
Then I would like to thank my parents and friends
who have helped me with their valuable suggestions
and guidance has been helpful in various phases of
the completion of the project.
4. Last but not the least I would like to thank my
classmates who have helped me a lot and also Sir
Lab attendant (NAME OF THE LAB ATTENDER).
DECLARATION
I hereby declare that project work entitled “ELECTRO
MAGNETIC INDUCTION”, submitted to the department of
Physics, Atomic Energy Central School (OSCOM) for the
subject Physics under the guidance of (NAME OF THE
SUBJECT TEACHER) is a record of original work done by
me. I further declare that this project or any part of it has not
been submitted elsewhere for any other class.
CLASS:_____________I
5. PLACE: NAME OF THE SCHOOL
DATE:
-: CONTENTS :-
1. INTRODUCTION
2. EXPERIMENT
3. THEORY
4. CONCLUSION
5. BIBLIOGRAPHY
6. INTRODUCTION:-
Electromagnetic induction is the production of a potential
difference (voltage) across a conductor when it is exposed to a
varying magnetic field. Faraday's law of induction is a basic law
of electromagnetism predicting how a magnetic field will interact with
an electric circuit to produce an electromotive force (EMF). It is the
fundamental operating principle of transformers, inductors, and many
types of electrical motors, generators and solenoids.
Electricity is carried by current, or the flow of electrons. One useful
characteristic of current is that it creates its own magnetic field. This
is useful in many types of motors and appliances.
Faraday’s Law of Electromagnetic Induction:-
It is a basic law of electromagnetism predicting how a magnetic field
will interact with an electric circuit to produce an electromotive force
(EMF). It is the fundamental operating principle of transformers,
inductors and many types of electrical motors and generators.
Faraday explained electromagnetic induction using the concept of lines
of force. These equations for electromagnetic induction are extremely
important since they provide a means to
precisely describe how, many natural physical
7. phenomena in our universe and behave.
FARADAY’S LAW:-
The induced electromotive force in any
closed circuit is equal to the negative of
the time rate of change of the magnetic flux through the circuit.
The ability to quantitatively describe physical phenomena not only
allows us to gain a better understanding of our universe, but it also
makes possible a host of technology innovations that define modern
society. Understanding Faraday’s laws of electromagnetic induction can
be beneficial since so many aspects of our daily life function because
of the principles behind Faraday’s law.
9. Faraday’s law describes electromagnetic induction. Whereby an
electric field is induced, or generated by a changing magnetic field.
In Faraday’s first experimental demonstration of electromagnetic
induction, he wrapped two wires around opposite sides of an iron ring or
‘torus’ to induce current.
Faraday’s law is a single equation describing two different phenomena:
the motional EMF generated by a magnetic force on a moving wire, and
the transformer EMF generated by an electric force due to a changing
magnetic field.
Electromagnetic Induction
10. EXPERIMENT
AIM:-
Observe how current can create a magnetic field.
MATERIALS:-
Thin copper wire
Long metal nail
12-V lantern battery
9-V battery
Wire cutters
Toggle switch
Electrical tape
Paper clips
11. CIRCUIT DIAGRAM:-
THEORY:-
The magnetic flux (𝝓 or 𝝓B) through a surface is the component
of the magnetic field passing through the surface.
The SI unit of magnetic flux is weber (Wb), and the CGS unit is
Maxwell.
Representation of Magnetic flux (𝜙) in a solenoid
12. Magnetic flux is usually measured with a flux meter, which
contains measuring coils and electronics that evaluate the change of
voltage in the measuring coils to calculate the magnetic flux.
If the magnetic field is constant, the magnetic flux passing through a
surface of vector area S is:-
𝝓B= 𝑩. 𝑺 = 𝑩𝑺𝒄𝒐𝒔𝜽
where 𝑩 is the magnitude of magnetic field having the unit of
Wb/m2
(T).𝑺 is the area of the surface and 𝜃 is the angle between
magnetic field lines and the normal.
For a varying magnetic field, we first consider the magnetic flux
through a small amount of area 𝑑𝑆 where we may consider the magnetic
field to be constant.
𝒅𝝓B= 𝑩. 𝒅𝑺
From the magnetic vector potential 𝐴 and the fundamental
theorem of the curl, the magnetic field may be defined as:-
𝝓B= ∮ 𝑨. 𝒅𝒍
𝜹𝑺
𝟎
where the line integral is taken over the boundary of the surface
𝑺, which is denoted as 𝜹𝑺.
13. LAW:-
The most widespread version of Faraday’s law of electromagnetic
induction states that
“The induced electromotive force in any closed surface is equal
to the negative of the rate of change of magnetic flux through the
circuit.”
This version of Faraday’s law strictly holds true only when the
closed circuit is a loop of infinitely thin wire, and is invalid in other
circumstances as discussed below. A different version, the Maxwell-
Faraday equation is valid in all circumstances, the magnetic flux (𝝓)
changes due to the change in magnetic field.
Faraday’s law of electromagnetic induction states that the wire
loop acquires an EMF, defined as the energy available per unit charge
that travels once around the wire loop.
Equivalently, it is the voltage that would be measured by cutting
the wire to create an open circuit and attaching a voltmeter to the
leads.
According to Lorentz force law,
𝑭 = 𝒒(𝑬 + 𝒗 × 𝑩)
And the EMF of the wire loop is
𝜺 =
𝟏
𝒒
∮ 𝑭. 𝒅𝒍
= ∮(𝑬 + 𝝂 × 𝑩)
14. where (i) 𝑬 is the electric field.
(ii) 𝑩 is the magnetic field.
(iii) 𝒅𝒍 is the infinite length along the wire.
And the line integral is evaluated along the wire.
The Maxwell-Faraday equation states that a time varying
magnetic field is always accompanied by spatially varying, non-
conservative electric field and vice versa. The Maxwell-Faraday
equation is:-
𝜵 × 𝑬 = −
𝜹𝑩
𝜹𝒕
where 𝜵 is the curl operatoe and again 𝑬(𝒓, 𝒕) is the electric field and
𝑩(𝒓, 𝒕) is the magnetic field. These fields can generally be functions
of position 𝒓 and time 𝒕.
The four Maxwell’s equations (including the Maxwell-Faraday
equation), along with the Lorentz force law are a sufficient foundation
to derive everything in classical electromagnetism.
Therefore, it is possible to “prove” Faraday’s law starting with
these equations. Faraday’s law could be taken as the starting point and
used to prove the Maxwell-Faraday equation and/or other laws.
15. PROCEDURE:-
1. Cut a long length of wire and attached one end to the positive
output of the toggle switch.
2. Twist the wire at least 50 times around the nail to create
a solenoid.
3. Once the wire has covered the nail, tape the wire to the negative
terminal of the 12V battery.
4. Cut a short piece of wire to connect the positive terminal of the
battery to the negative terminal of the toggle switch.
5. Turn on the switch.
6. Bring paper clips close to the nail. What happens? How many
paper clips can you pick up?
7. Repeat the experiment with the 9V battery.
8. Repeat the experiment with the 9V and 12V batteries arranged in
series.
RESULTS:-
The current running through the circuit will cause the nail to be
magnetic and attract paper clips. The 12V battery will create a
stronger magnet than the 9V battery. The series circuit will create a
stronger magnet than the individual batteries did.
Why?
Electric currents always produce their own magnetic fields. This
phenomenon is represented by the right-hand-rule. If you make the
“Thumbs-Up” sign with your hand like this:
16. The current will flow in the direction the thumb is pointing, and
the magnetic field direction will be described by the direction of the
fingers. This means when you change the direction of the current, you
also change the direction of the magnetic field. Current flows (which
means electrons flow) from the negative end of a battery through the
wire to the positive end of the battery, which can help you determine
what the direction of the magnetic field will be.
When the toggle switch is turned on, the current will flow from
the negative terminal of the battery around the circuit to the positive
terminal. When the current passes through the nail it induces, or
creates, a magnetic field. The 12V battery produces a larger voltage;
therefore, produces a higher current for a circuit of the same
resistance. Larger currents will induce larger (and stronger) magnetic
fields, so the nail will attract more paperclips when using a larger
voltage.
Conclusion:-
Faraday’s law of electromagnetic induction, first observed and
published by Michael Faraday in the mid-nineteenth century, describes
a very important electromagnetic concept. Although its mathematical
representations are cryptic, the essence of Faraday’s law is not hard
to grasp. It relates an induced electric potential or voltage to a
dynamic magnetic field. This concept has many far reaching
ramifications that touch our lives in many ways: from shining of the sun
to electricity and power in our homes. We can all appreciate the
profound impact Faraday’s law has on us.
17. The principles of electromagnetic induction are applied in
many devices and systems, including:
Current clamp
Electrical generators
Electromagnetic forming
Graphics tablet
Hall effect meters
Induction cookers
Induction motors
Induction sealing
Induction welding
Inductive charging
Inductors
Magnetic flow meters
Mechanically powered flashlight
Pickups
Rowland ring
Transcranial magnetic stimulation
Transformers
Wireless energy transfer
