# Faraday's law of induction

Basic law of electromagnetism predicting how a magnetic field will interact with an electric circuit to produce an electromotive force (emf)—a phenomenon known as electromagnetic induction.

- Faraday's law of induction145 related topics

## Lorentz force

Combination of electric and magnetic force on a point charge due to electromagnetic fields.

Variations on this basic formula describe the magnetic force on a current-carrying wire (sometimes called Laplace force), the electromotive force in a wire loop moving through a magnetic field (an aspect of Faraday's law of induction), and the force on a moving charged particle.

## Magnetic flux

Surface integral of the normal component of the magnetic field B over that surface.

The relationship is given by Faraday's law:

## Electromotive force

Electrical action produced by a non-electrical source, measured in volts.

The general principle governing the emf in such electrical machines is Faraday's law of induction.

## Electric generator

Device that converts motive power into electric power for use in an external circuit.

The principle, later called Faraday's law, is that an electromotive force is generated in an electrical conductor which encircles a varying magnetic flux.

## Maxwell's equations

Maxwell's equations are a set of coupled partial differential equations that, together with the Lorentz force law, form the foundation of classical electromagnetism, classical optics, and electric circuits.

The Maxwell–Faraday version of Faraday's law of induction describes how a time-varying magnetic field corresponds to rotation of an electric field.

## Electromagnetic induction

Production of an electromotive force across an electrical conductor in a changing magnetic field.

Michael Faraday is generally credited with the discovery of induction in 1831, and James Clerk Maxwell mathematically described it as Faraday's law of induction.

## Transformer

Passive component that transfers electrical energy from one electrical circuit to another circuit, or multiple circuits.

Faraday's law of induction, discovered in 1831, describes the induced voltage effect in any coil due to a changing magnetic flux encircled by the coil.

## Inductor

Passive two-terminal electrical component that stores energy in a magnetic field when electric current flows through it.

When the current flowing through the coil changes, the time-varying magnetic field induces an electromotive force (e.m.f.) (voltage) in the conductor, described by Faraday's law of induction.

## Michael Faraday

English scientist who contributed to the study of electromagnetism and electrochemistry.

His demonstrations established that a changing magnetic field produces an electric field; this relation was modelled mathematically by James Clerk Maxwell as Faraday's law, which subsequently became one of the four Maxwell equations, and which have in turn evolved into the generalization known today as field theory.

## Lenz's law

Such that the magnetic field created by the induced current opposes changes in the initial magnetic field.

Lenz's law is contained in the rigorous treatment of Faraday's law of induction (the magnitude of EMF induced in a coil is proportional to the rate of change of the magnetic field), where it finds expression by the negative sign: