mutual inductance

physics

Also known as: mutual induction

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July 1, 2026

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Mutual inductance is the measure of the inductance between two circuits. It describes how a changing current in one circuit induces a voltage in a second, adjacent circuit. This phenomenon is a key aspect of electromagnetic induction, first demonstrated by Michael Faraday.1234

A device designed to provide mutual inductance is called a mutual inductor, typically consisting of two coils not electrically connected. The strength of this inductive coupling depends on factors like the proximity and orientation of the circuits, with maximum mutual inductance occurring when the magnetic fields of the circuits align closely. This principle is fundamental to devices like transformers, which utilize mutual inductance to change voltage levels in alternating current (AC) circuits.53

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electromagnetism
Self-inductance and mutual inductance
The self-inductance of a circuit is used to describe the reaction of the circuit to a changing current in the circuit, while the mutual inductance with respect to a second circuit describes the reaction to a changing current in the second circuit. When…
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The self-inductance of a circuit is used to describe the reaction of the circuit to a changing current in the circuit, while the mutual inductance with respect to a second circuit describes the reaction to a changing current in the second circuit. When…
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inductance
…changing, the phenomenon is called mutual induction, exemplified in a transformer. A changing magnetic field caused by a varying current in a conductor, however, also induces an electromotive force in the very conductor that carries the changing current. Such a phenomenon is called self-induction, and the quotient of the induced…
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…changing, the phenomenon is called mutual induction, exemplified in a transformer. A changing magnetic field caused by a varying current in a conductor, however, also induces an electromotive force in the very conductor that carries the changing current. Such a phenomenon is called self-induction, and the quotient of the induced…
Read More