ABSTRACT
This chapter presents alternating current (a.c.) and voltages, with its terminology and values and its sinusoidal expression. It explores why a.c. is used in preference to direct current (d.c.) The chapter describes the principle of operation of an a.c. generator. It examines methods of smoothing a rectified output waveform. With a.c. the flow of electric charge periodically reverses direction, whereas with d.c. the flow of electric charge is only in one direction. The resultant voltage is always 'alternating'by virtue of the magnet's rotation. A.c. is the form in which electric power is delivered to businesses and residences. The usual waveform of an a.c. power circuit is a sine wave. Alternating voltage can be carried around the country via cables far more effectively than direct current because a.c. can be passed through a transformer and a high voltage can be reduced to a low voltage, suitable for use in homes.
