Magnetomotive force is any physical cause that produces magnetic flux. Magnetic flux, represented by the Greek letter Φ ( Phi) is a measure of quantity of Magnetism, taking into account the strength and the extent of a Magnetic In other words it is a field of magnetism(tesla) that has area(meters square), so that (Tesla)(Area)= Flux. It is analogous to electromotive force or voltage in electricity. Electromotive force ( emf, \mathcal{E} is a term used to characterize electrical devices such as Voltaic cells thermoelectric devices electrical Electrical tension (or voltage after its SI unit, the Volt) is the difference of electrical potential between two points of an electrical MMF usually describes electric wire coils in a way so scientists can measure or predict the actual force a wire coil can generate.

In this context, the word "force" is used in a general sense of "work potential", and is analogous to, but distinct from mechanical force measured in newtons. In Physics, a force is whatever can cause an object with Mass to Accelerate. The newton (symbol N) is the SI derived unit of Force, named after Isaac Newton in recognition of his work on Classical

The standard definition of magnetomotive force involves current passing through an electrical conductor, which accounts for the magnetic fields of electromagnets as well as planets and stars. In Science and engineering, a conductor is a material which contains movable Electric charges. An electromagnet is a type of Magnet in which the Magnetic field is produced by the flow of an electric current. A planet, as defined by the International Astronomical Union (IAU is a celestial body Orbiting a Star or stellar remnant that is A star is a massive luminous ball of plasma. The nearest star to Earth is the Sun, which is the source of most of the Energy on Earth Permanent magnets also exhibit magnetomotive force, but for different reasons. A magnet (from Greek grc μαγνήτης λίθος " Magnesian stone" is a material or object that produces a Magnetic field.

## Units

The unit of magnetomotive force is the ampere-turn (At), represented by a steady, direct electric current of one ampere flowing in a single-turn loop of electrically conducting material in a vacuum. The ampere-turn (AT is the MKS unit of Magnetomotive force, represented by a Direct current of one Ampere flowing in a single-turn loop in Electric current is the flow (movement of Electric charge. The SI unit of electric current is the Ampere. The ampere, in practice often shortened to amp, (symbol A is a unit of Electric current, or amount of Electric charge per second This vacuum means "absence of matter" or "an empty area or space" for the cleaning appliance see Vacuum cleaner.

The gilbert (Gi), established by the IEC in 1930 [1], is the CGS unit of magnetomotive force. Year 1930 ( MCMXXX) was a Common year starting on Wednesday (link will display 1930 calendar of the Gregorian calendar. The centimetre-gram-second system ( CGS) is a system of physical units. The gilbert is defined differently, and is a slightly smaller unit than the ampere-turn. The unit is named after William Gilbert (1544 - 1603) English physician and natural philosopher. William Gilbert, also known as Gilbard ( Colchester, England, May 24, 1544 &ndash London, England, November 30

$\begin{matrix}1\,\operatorname{Gi} & = & {\frac {10} {4\pi}} \ \mbox{AT} \\ & \approx & 0.795773 \ \mbox{AT}\end{matrix}$

## Equations

The magnetomotive force $\mathfrak F$ in an inductor is given by:

$\mathfrak F = N I$

and

$\mathfrak F = \Phi \mathfrak R$

where N is the number of turns of the coil, I is the current in the coil, Φ is the magnetic flux and $\mathfrak R$ is the reluctance of the magnetic circuit. Magnetic reluctance or "magnetic resistance" is analogous to resistance in an Electrical Circuit (although it does not dissipate magnetic The latter equation is sometimes known as Hopkinson's law. Hopkinson's law is the Magnetic counterpart to the electrical Ohm's law.

## Magnetomotive force in a generator

A spinning magnet produces a magnetic flux. In the presence of a generator coil, the rotational energy of a spinning magnet is converted into electricity inside the coil. The voltage induced in the coil is proportional to the coil's number of turns while the current induced in the coil is inversely proportional to its resistance (or more generaly, its impedance). Therefore the power induced inside a coil with respect to a changing external magnetic field increases in proportion to the number of turns and the amperage induced in the coil. This can also be thought in terms of the ratio of power generated divided by the rate of cycling, or rotational speed, the quotient of which is torque. In Mathematics, a quotient is the result of a division. For example when dividing 6 by 3 the quotient is 2 while 6 is called the dividend, and 3 the A torque (τ in Physics, also called a moment (of force is a pseudo- vector that measures the tendency of a force to rotate an object about

## magnetomotive force

### -noun

1. (physics) the force associated with a magnetic field and that produces magnetic flux; it is the work required to carry a magnetic monopole of unit strength once round a magnetic circuit; measured in ampere-turns
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