The theory underlying an a.c. generator's operation is __________

AC generators work on the principle of Faraday’s law of electromagnetic induction.

Its principle states that a current-carrying conductor that cuts a uniform magnetic field produces electromotive force, also known as voltage. This can either be achieved by rotating a conducting coil in a static magnetic field or rotating the magnetic field containing the stationary conductor. It is simpler to extract induced alternating current from a stationary armature coil than from a revolving coil, keeping the coil fixed is the ideal arrangement.