magnetomotive force (magnetic potential)
Magnetomotive force, also known as magnetic potential, is the property of certain substances or phenomena that gives rise to magnetic field s. Magnetomotive force is analogous to electromotive force or voltage in electricity.
The standard unit of magnetomotive force is the ampere-turn (AT), represented by a steady, direct electrical current of one ampere (1 A) flowing in a single-turn loop of electrically conducting material in a vacuum . Sometimes a unit called the gilbert (G) is used to quantify magnetomotive force. The gilbert is defined differently, and is a slightly smaller unit than the ampere-turn. To convert from ampere-turns to gilberts, multiply by 1.25664. Conversely, multiply by 0.795773.
Although the standard definition of magnetomotive force involves current passing through an electrical conductor, permanent magnet s also exhibit magnetomotive force. The same is true for planets with magnetic fields, such as the Earth, Jupiter, Saturn, Uranus, and Neptune. The Sun also generates magnetomotive forces, particularly in the vicinity of sunspots.
Also see ampere-turn , gilbert , magnetic field , electromotive force , International System of Units ( SI ), and Table of Physical Units .