What is the main function of a transformer in an electrical circuit?

The main function of a transformer in an electrical circuit is to change the voltage level of the electrical current passing through it. Transformers operate on the principle of electromagnetic induction, where alternating current (AC) flows through one coil of wire (the primary winding), creating a magnetic field that induces a voltage in another coil (the secondary winding). This allows transformers to either step up (increase) or step down (decrease) voltage levels, while keeping the power (minus losses) relatively constant.

For example, in power distribution systems, transformers are essential for stepping up voltage from power plants for efficient long-distance transmission and then stepping it down for safe distribution to homes and businesses. This capability makes transformers vital components in managing electrical energy effectively and safely within various applications.