The force that sets up the magnetic field depends on the quantity of turns on the coil and also the magnitude of the electric current flowing. This force is termed the magneto electric machine driver and also the unit of measure is that the Ampere-Turn. This equals the electric current times the quantity of turns. (MMF = I x n). The magneto motive force is also referred to as Hopkinson's law.
The Ampere-turn (At), delineated by a gradual, direct current of one ampere flowing during a single-turn loop of electrically conducting material during a vacuum.
The gilbert (Gi), established by the IEC in 1930 , is that the CGS system unit of force. The gilbert is outlined otherwise, and may be a slightly smaller unit than the magneto motive force. The unit is known as when William Gilbert (1544–1603) English physician and natural thinker.
The magneto motive force in an inductor is given by:
F = NI
Where N is the no. of turns in the coil and
I is the current through the electric circuit.
F = ΦR
Where Φ is the magnetic flux
R is the reluctance.
F = Hl
Where H is the magnetizing force (magnetizing field strength)
l is the mean length of the circumference of a toroid or a solenoid.
Magneto motive force in a generator
A spinning magnet creates a magnetic flux. Within the presence of a generator coil, the motility energy of a spinning magnet is converted into electricity within the coil. The voltage evoked within the coil is proportional to the coil's number of turns whereas the electric current induced within the coil is reciprocally proportional to its resistance (or additional usually, its electrical phenomenon, measured in ohms). So the power induced within a coil with relevance a dynamical external field of force will increase in proportion to the no. of turns and also the electrical phenomenon evoked within the coil. This may even be thought in terms of the quantitative relation of power generated divided by the rate of frequency, or motility speed, the quotient of that is torsion.
Although the general definition of mmf involves current passing through an electrical conductor, static magnet s conjointly exhibit magneto motive force.