What does a transformer do with electricity?

A transformer functions by altering the voltage of an alternating current (AC) while maintaining the overall power within the system. This process is based on the principles of electromagnetic induction, where the input voltage is transformed to a different voltage on the output side through coils of wire (windings). The relationship between the primary (input) and secondary (output) voltage is determined by the ratio of the turns of wire in the primary winding compared to the secondary winding.

In terms of power, the principle of conservation states that the power input to the transformer is equal to the power output (minus any losses), meaning that if the transformer increases the voltage, the current will proportionally decrease to keep the power level consistent. This ability to step up or step down voltage levels is crucial in power distribution and transmission, allowing electrical energy to travel efficiently over long distances, and then be appropriately reduced for safe use in homes and businesses.

The other options do not accurately describe the primary function of a transformer. While frequency adjustments, current regulation, and the conversion from AC to DC are essential electrical engineering concepts, they do not describe the fundamental operation of a transformer.