What is the role of a transformer in an AC circuit?

A transformer is used to change the voltage of an AC circuit.

Transformers are used in AC circuits to change the voltage of the electrical supply. They consist of two coils of wire, known as the primary and secondary coils, which are wrapped around a magnetic core. When an AC voltage is applied to the primary coil, it creates a magnetic field which induces a voltage in the secondary coil. The ratio of the number of turns in the primary and secondary coils determines the voltage transformation ratio.

Transformers are used for a variety of purposes in AC circuits. They are used to step up or step down the voltage of the electrical supply, which is necessary for transmitting electrical power over long distances. They are also used in power supplies to provide a stable output voltage, and in electronic circuits to isolate different parts of the circuit from each other.

Transformers are highly efficient, with very little energy loss during the voltage transformation process. They are also very reliable, with no moving parts and a long lifespan. However, they are only suitable for use with AC circuits, and cannot be used with DC circuits.