magnetomotive force

physics

Also known as: mmf

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Last updated

June 30, 2026

Quick Summary

Magnetomotive force (MMF) is the cause of magnetic flux in a magnetic circuit. It is analogous to electromotive force (voltage) in an electric circuit. MMF is created by an electric current flowing through a coil of wire. The strength of the MMF is proportional to the number of turns in the coil and the amount of current. It is measured in units of ampere-turns. MMF drives magnetic flux, which is similar to how voltage drives electric current.12

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magnetic circuit
The magnetomotive force, mmf or f, is analogous to the electromotive force V and may be considered the factor that sets up the flux. The mmf is equivalent to a number of turns of wire carrying an electric current and has units of ampere-turns. If either…
Read More
The magnetomotive force, mmf or f, is analogous to the electromotive force V and may be considered the factor that sets up the flux. The mmf is equivalent to a number of turns of wire carrying an electric current and has units of ampere-turns. If either…
Read More