What is the purpose of a transformer in an electrical circuit?

The purpose of a transformer in an electrical circuit is to increase or decrease voltage levels. Transformers operate on the principle of electromagnetic induction and allow for the efficient transmission of electrical energy over long distances by adjusting the voltage to a suitable level for either transmission or usage.

In practical terms, when the voltage is increased, it reduces the current flowing through the circuit, which in turn minimizes energy loss as heat in the wires. Conversely, when the voltage is decreased, it allows for the safe use of electricity at lower voltages suitable for consumer devices and appliances. This ability to step voltage up or down is critical for the functioning of power distribution systems, making transformers essential components in electrical engineering and energy management.

Transformers do not convert AC to DC power; that function is typically performed by rectifiers. They also do not store electrical energy; storage is typically managed by batteries or capacitors. Additionally, transformers do not measure electrical resistance; this task is carried out using multimeters or ohmmeters. This unique property of voltage transformation is why the first option is the correct response.