What is the purpose of a transformer?

A transformer serves the essential purpose of increasing or decreasing voltage levels in an electrical circuit. This is particularly important in the transmission of electrical energy because it allows electricity to be transmitted over long distances with minimal energy loss. By adjusting the voltage levels, transformers enable power to be efficiently transmitted from power plants to homes and businesses.

When the voltage is increased (step-up transformer), it allows the current to decrease, which reduces the energy lost as heat during transmission. Conversely, when the voltage is decreased (step-down transformer), it makes the electricity safe and usable for consumers. This ability to modify voltage levels while maintaining the overall power flow is crucial for efficient and safe electrical distribution.

The other options represent different functions: protecting circuits from overload is a role of circuit breakers or fuses, storing electrical energy is typically done by capacitors or batteries, and measuring electrical current is the function of ammeters. Each of these plays an important role in electrical systems, but they do not pertain to the specific function of a transformer.