ELECTROMAGNETIC INDUCTION

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This is to certify that Name of Student of 12th

science has completed his project entitled on “ELECTROMAGENTIC INDUCTION” during the academic year 2013-2014 for his partial fulfillment of his academic course.

To the best of my knowledge, the subject matter present in the project is original and bonafide in nature.

Date: -

Project Guide: - Teacher’s Name

Place: - School Name

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First and foremost I would like to thanks my teacher Teacher’s Name for his constant guidance and support.

I would also like to extend my sincere gratitude to Mr. B.R.Solanki (Lab Attender) who has helped me in the successful completion of my project entitled

“ELECTROMAGENTIC INDUCTION”.

Signature:-

Name of Student12th A

(Science)

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

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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: - 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 principles of

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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

AIM

Observe how current can create a magnetic field.

MATERIALS Thin copper wire Long metal nail

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12-V lantern battery 9-V battery Wire cutters Toggle switch Electrical tape Paper clips

CIRCUIT DIAGRAM

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PPROCEDURE1. 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.

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RESULTSThe 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:

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.

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Comprehensive Physics Laboratory Manual Class XII

http://www.google.com.in/

http://www.answers.yahoo.com/

http://www.wikipedia.org/

http://www.icbse.com/

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