What is the primary function of a transformer?

The primary function of a transformer is to change the voltage of electricity. This is achieved through the principle of electromagnetic induction, which allows a transformer to convert alternating current (AC) from one voltage level to another. Transformers can either step up (increase) or step down (decrease) voltage levels, depending on the winding ratio of the primary and secondary coils.

By altering the voltage, transformers play a critical role in the efficient transmission of electrical power over long distances, minimizing energy losses. In power distribution systems, they ensure that electricity can be transmitted at high voltages to reduce current and thus lower resistive losses, then transform it to lower voltages suitable for domestic or industrial use.

The other options, while related to electrical systems, do not capture the primary function of a transformer. Maintaining a voltage level pertains more to voltage regulators, regulating the flow of electricity relates to circuit breakers or fuses, and measuring electric current is the function of ammeters or other measurement devices. This clarity delineates the transformer’s specific role in electrical systems.