Question

Write the principle of working of an ac generator. Draw its labelled diagram and explain its working.

Answer 1

Principle of Working of an AC Generator:

The principle of working of an AC generator is based on the phenomenon of electromagnetic induction. According to Faraday’s law of induction, when a conductor is rotated in a magnetic field, an emf (electromotive force) is induced in the conductor. The direction of this induced emf changes with time as the conductor rotates, producing an alternating current (AC).

The generator consists of a coil of wire that rotates in a magnetic field, and the voltage generated is directly related to:

• The speed of rotation,
• The strength of the magnetic field, and
• The number of turns in the coil.

The generator works on the principle of electromagnetic induction:

• A coil of wire is rotated in a magnetic field.
• As the coil cuts the magnetic lines of flux, an emf is induced in the coil, which causes current to flow.
• The induced emf alternates as the coil rotates, hence the current produced is alternating (AC).
• The direction of current alternates as the coil passes through different positions in the magnetic field.