ABSTRACT
Alternating electrical voltages and currents are produced for mains electrical supplies. The reason for this is because AC is easier to generate than DC supplies. The basic principle relies on the generation of an EMF when a magnetic field changes within a coil of wire. This effect was first demonstrated by Faraday in 1831, as shown in Figure 38.40. As the north pole of the magnet moves downwards, the galvanometer deflects to the right and, as it moves upwards, it deflects to the left.
