The a.c. generator — Describe

Describe the construction and operation of a simple a.c. generator.

A simple a.c. generator consists of a coil that rotates within a magnetic field (or, alternatively, a magnet that rotates inside a fixed coil). As the coil rotates, it cuts through the magnetic field lines, inducing an alternating e.m.f. across its ends. Slip rings, fixed to and rotating with the ends of the coil, together with fixed carbon brushes pressed against them, maintain continuous electrical contact with the external circuit as the coil turns, allowing the alternating current to be delivered.