What is the primary use of a transformer in electrical circuits?

The primary use of a transformer in electrical circuits is to convert voltage levels. Transformers operate on the principle of electromagnetic induction, which allows them to step up or step down alternating current (AC) voltages. By altering the number of turns in the primary and secondary coils of the transformer, it can increase or decrease voltage while maintaining the power (neglecting losses).

For instance, in power distribution systems, high voltages are used to transmit electricity over long distances to reduce energy loss. At the consumption point, transformers step down the high voltage to safer, usable levels for homes and businesses. This function is crucial for efficient energy transmission and distribution, making transformers indispensable in electrical engineering and power systems.

The other options, while they might describe components used in electrical circuits, do not capture the fundamental role of transformers. For example, storing electrical energy is more aligned with capacitors or batteries. The idea of increasing current flow is not accurate, as transformers don't increase current; rather, the relationship between voltage and current is such that increasing voltage results in a proportional decrease in current, maintaining the power balance. Finally, acting as a switch does not apply to transformers, as they do not function as devices for turning circuits on or off but rather as devices