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Magnetic Induction Formula

In this article we will discuss the magnetic induction formula, Faraday's law of magnetic induction formula, how to demonstrate electromagnetic induction and more.

The creation of an electromotive force across an electrical conductor in a changing magnetic field is known as electromagnetic or magnetic induction.

Induction was discovered in 1831 by Michael Faraday, and it was mathematically characterised as Faraday’s law of induction by James Clerk Maxwell. Lenz’s law describes the direction of the induced field. The Maxwell–Faraday equation, one of Maxwell’s four electromagnetic equations, was derived from Faraday’s law. Electrical components like inductors and transformers, as well as devices like electric motors and generators, have all benefited from electromagnetic induction.

Magnetic induction

Magnetic induction is the property through which an ordinary piece of iron gets magnetic properties temporarily as a result of the presence of another close magnet . The phenomenon of magnetization of materials in an external magnetic field is known as magnetic induction. Materials acquire magnetic characteristics as a result of this magnetization. Electricity and magnetism are two ideas that are interconnected. Moving electric charges (electric current) cause magnetic fields, as scientists discovered about 200 years ago. When moving magnets generate electric currents, the opposite is also true.

Electricity and Magnetism

Electricity and magnetism are two ideas that are interconnected. Moving electric charges (electric current) cause magnetic fields, as scientists discovered about 200 years ago. Likewise, the inverse is true. Electric currents are generated by moving magnets. Experiments by Michael Faraday and Joseph Henry proved decisively that when closed coils were exposed to changing magnetic fields, electric currents were induced. Electromagnetic Induction is the name given to this occurrence.

Magnetic Flux

The magnetic flux is the number of magnetic field lines that connect a surface with a cross-sectional area of A. The product of the magnetic flux density normal to the surface and the area of the surface determines the magnetic flux through a small surface. Magnetic flux is defined in the same way as electric flux: ∅B=BAcos

here ∅ is angle between two media.

Magnetic flux is a scalar quantity that has only magnitude. Its unit is Weber.

Faraday’s Law Of Induction

Faraday’s law of induction describes how an electric current generates a magnetic field and a changing magnetic field generates an electric current in a conductor. As per the University of Texas at Austin, English scientist Michael Faraday is credited with discovering magnetic induction in 1831, despite the fact that American physicist Joseph Henry independently discovered the phenomenon about the same time.

Faraday’s observed that as the magnetic flux through a coil changes with time, an emf is induced in the coil.  According to this law the pace of change of magnetic flux in a circuit induces an emf in it. The rate of change of magnetic flux through a circuit determines the magnitude of the induced emf in that circuit.

In mathematics term it is written as: ε= -d∅dt

The minus symbol implies that something is going in the wrong direction.

In a closed loop, this determines the direction of current. Because the change of flux associated with each turn in a tightly wound coil of N turns is the same, the total induced emf is given by:

 ε= -Nd∅dt

Electromagnetic induction

Michael Faraday discovered this concept in 1831, and James Clerk Maxwell mathematically characterised it as Faraday’s law of induction. But, before we get any further, it’s important to understand what Electromagnetic Induction is.

The current produced by the voltage produced by a changing magnetic field is known as electromagnetic induction. This occurs in one of two scenarios:- When the conductor is placed in a changing magnetic field, When a conductor moves constantly in a static field.

Michael Faraday did an experiment in which he wrapped the wires around a bar magnet and linked them to a voltmeter (a device that measures voltage). He then shifted the magnet and observed the voltage variations. He came to certain conclusions after doing the studies.

The number of coils determines the induced voltage, which is equivalent to the number of wire turns. The voltage produced increases as the number of turns increases.

Change in Magnetic Field – Any change in the magnetic field has an impact on voltage production. Moving the magnet around the conductor or vice versa causes changes in the magnetic field.

Formula

The formula will be given as:

 ε= -Nd∅dt

Here is induced emf

N is the no of turns

∅ is the magnetic flux

t is the time

Applications of Electromagnetic Induction

This theory is essential to the operation of an AC generator.

The principle of induction is used in transformers.

Conclusion

The creation of an electromotive force across an electrical conductor in a changing magnetic field is known as electromagnetic or magnetic induction. Electrical components like inductors and transformers, as well as devices like electric motors and generators, have all benefited from electromagnetic induction. Electricity and magnetism are two ideas that are interconnected. The phenomenon of magnetization of materials in an external magnetic field is known as magnetic induction. The magnetic flux is the number of magnetic field lines that connect a surface with a cross-sectional area of A.The rate of change of magnetic flux through a circuit determines the magnitude of the induced emf in that circuit.

In mathematics term it is written as: ε= -d∅dt

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Frequently Asked Questions

Get answers to the most common queries related to the JEE Examination Preparation.

Define magnetic induction.

Ans. The process through which a magnetic field magnetises a substance such as...Read full

Who gives the magnetic induction theory?

Ans. Michael faraday.

Write the application of magnetic induction.

Ans.  It is used in transformer, AC generators.

Write the unit of magnetic induction.

Ans. Tesla