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Faraday’s Law

Faraday’s Law is a fundamental law of electromagnetism that describes the interaction between electricity and magnetism. The law was discovered by Michael Faraday in 1831.

Faraday's Law

According to Faraday’s Law, a changing magnetic flux through a closed electric circuit induces an electric current in that circuit. The magnitude of the induced current is proportional to the rate of change of the magnetic flux and the number of turns in the circuit.

Formally, Faraday’s Law can be expressed as follows: the electromotive force (EMF) induced in a closed circuit is proportional to the rate of change of the magnetic flux passing through the circuit.

This is expressed in Faraday’s EMF equation:

ε = -dΦ/dt


ε – electromotive force induced in the circuit

Φ – magnetic flux

dt – change in time.

The negative sign in the equation indicates that the EMF is induced in a direction that opposes the change in magnetic flux.

Applications of Faraday’s Law

Faraday’s Law finds wide applications in various fields, including electrical engineering, electronics, physics, chemistry, and other sciences related to electromagnetism.

One of the most common applications is in the generation of electricity. Electric generators, such as those used to produce electricity for homes and industries, rely on Faraday’s Law to generate electric power. The generator contains a coil of wire that rotates in a magnetic field. As the coil rotates, the changing magnetic field induces an electric current in the wire.

Another application of Faraday’s Law is in transformers. A transformer is a device that transfers electric energy from one circuit to another through electromagnetic induction. Transformers consist of two coils of wire, one connected to the source of alternating current and the other to the load. The changing magnetic field created by the alternating current in the first coil induces a current in the second coil, which is used to power the load.

Faraday’s Law also plays a crucial role in the propagation of electromagnetic waves. Electromagnetic waves are generated when electric and magnetic fields oscillate in phase with each other. These waves are used in various technologies, such as radio communication and wireless networks.

In conclusion, Faraday’s Law of electromagnetic induction is a fundamental principle that underlies many modern technologies. Its applications range from electricity generation to wireless communication, making it one of the most important discoveries in the field of electromagnetism.