What is Faraday's law of induction?

Faraday's law of induction is a fundamental law of electromagnetism describing how changing magnetic fields can induce an electric current or electromotive force. In literature, it generally refers to two distinct statements: the Maxwell-Faraday equation involving time-varying magnetic fields, and Faraday's flux rule relating electromotive force to magnetic flux changes. Michael Faraday discovered induction in 1831, and James Clerk Maxwell later provided its mathematical description.

What we know

• Faraday's law of induction describes how a changing magnetic field can induce an electric current in a circuit. [2]
• The Maxwell-Faraday equation states that a time-varying magnetic field is accompanied by a circulating electric field without requiring a physical circuit. [2]
• Faraday's flux rule relates the electromotive force around a closed loop to the time rate of change of magnetic flux through that loop. [2]
• Michael Faraday discovered electromagnetic induction in 1831. [3, 4]

Still open

• The literature uses Faraday's law to refer to two closely related but technically distinct statements.

Where to go next

• how it workedHow does electromagnetic induction work in transformers?
• the bigger pictureWhat are Maxwell's equations?
• whoWho was Michael Faraday?
• how we knowWhat is the Faraday paradox?
• a case in pointWhat is a homopolar generator?
• an unexpected connectionHow does special relativity explain motional and transformer emf?Special relativity resolves a historical conceptual problem by showing that the distinction between motional emf and transformer emf is frame-dependent.

Sources

• [1]Faraday's law of induction (Wikidata Q181465) · CC0 1.0
• [2]Faraday's law of induction · CC BY-SA 4.0
• [3]Electromagnetic induction · CC BY-SA 4.0
• [4]Faraday paradox · CC BY-SA 4.0
• [5]Homopolar generator · CC BY-SA 4.0