ABSTRACT
The electric circuit quantity of voltage or electromotive force (EMF) is analogous to the magnetic circuit quantity of magnetomotive force (MMF). This chapter describes the quantities describing the magnetic field and gives the mathematical expression and its units used to measure them. Magnetic path is one of the most important parts of the magnetic circuit and is usually made of a highly suitable ferromagnetic material for magnetization in the form of a closed loop, often different, for example, a circular ring or square or rectangular frame. The placing of the coil within a variable magnetic field, or moving the coil within a static magnetic field leads to the generation of electric motive force, and this is the principle of all generators. Also, when placing a metal object within the range of magnetic variable, the electric motive force will urge in the example of what happens in the coil or connector.
