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

A transformer primarily functions to change the voltage level in an electrical circuit. It operates on the principle of electromagnetic induction and comprises two coils, known as the primary and secondary windings, wound around a core. When alternating current flows through the primary coil, it creates a magnetic field that induces a voltage in the secondary coil.

The voltage transformation depends on the turns ratio of the coils; if the secondary coil has more turns than the primary, the voltage increases (step-up transformer) and if it has fewer turns, the voltage decreases (step-down transformer). This ability to increase or decrease voltage is essential for the efficient transmission and distribution of electrical power, allowing high voltage for long-distance transmission to minimize energy loss and then stepping it down to a lower voltage for safe use in homes and businesses.

While regulating current and maintaining voltage levels are important features in electrical systems, these functions are not the primary role of a transformer. A transformer does not change resistance levels, as resistance is a characteristic of materials and components in the circuit rather than something transformed by a transformer.