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write a note on induction of current in a coil

Dear student ,
We can indue the current in a coil by two ways .
1. By Moving the coil towards the magnet 
When the north pole of a magnet is approaching towards the coil the magnetic flux associated with the coil will increase and according to the Faraday's law of electromagnetic induction due to the change in flux emf and current will induce in the coil and this current will create its own magnetic field .Now according to Lenz's law this magnetic field created will oppose the increase in flux  through the coil and it is only possible when the coil side attains north polarity as similar poles repel each other .After knowing the magnetic polarity of the coil side we can determine the direction of the induced current by applying right hand rule .Hence current will be in anti clockwise direction .



2. By Moving the coil away from the Magnet 
Now when this north pole is moving away from the coil the magnetic flux linking to the coil will decrease .Again according to the Faraday's law of electromagnetic induction an emf and current will induce in the coil and this current will create its own magnetic field . Now according to Lenz's law this created magnetic field will oppose the decrease in flux through the coil and this is only possible when the approaching coil side attains south polarity as we know that the opposites poles attract each other .Once we know the magnetic polarity of the coil side we can easily determine the direction of induced current by applying right hand rule . Hence the current will be in clockwise direction .


Regards

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An induction coil or "spark coil" (archaically known as an inductorium orRuhmkorff coil[1] after Heinrich Ruhmkorff) is a type of electrical transformerused to produce high-voltage pulses from a low-voltage direct current (DC) supply.[1][2] To create the flux changes necessary to induce voltage in the secondary coil, the direct current in the primary coil is repeatedly interrupted by a vibrating mechanical contact called an interrupter.[1] Development began in 1836 by Nicholas Callan, Charles Page and others.[1] The induction coil was the first type of transformer and they were widely used in x-ray machines,[1][3]spark-gap radio transmitters,[1][3] arc lighting and quack medicalelectrotherapy devices from the 1880s to the 1920s. Today their only common use is as the ignition coils in internal combustion engines and in physics education to demonstrate induction.

The term 'induction coil' is also used for a coil carrying high-frequencyalternating current (AC), producing eddy currents to heat objects placed in the interior of the coil, in induction heating or zone melting equipment.
 

  Antique induction coil used in schools, from around 1900, Bremerhaven, Germany
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All copy paste.`
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Exactly just copy and paste
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