What is the function of an electrical transformer?

The function of an electrical transformer is primarily to increase or decrease voltage levels in an alternating current (AC) electrical system. Transformers operate based on the principle of electromagnetic induction, utilizing coils of wire (windings) that create a magnetic field when an AC current flows through them.

When electrical voltage is applied to the primary winding, it produces a magnetic field that induces a current in the secondary winding. The ratio of the number of turns in the primary winding to the number of turns in the secondary determines whether the voltage is stepped up or stepped down. For instance, if the secondary winding has more turns than the primary, the transformer increases the voltage; conversely, if there are fewer turns in the secondary, the voltage is decreased.

This capability to modify voltage levels is essential for efficient power transmission and distribution, allowing electricity to be transmitted over long distances while minimizing energy loss, and enabling the use of electrical devices that require different voltage levels for operation. In this context, the other choices do not accurately represent the primary function of a transformer. For instance, converting AC to DC pertains to rectifiers, while storing electrical energy relates to capacitors or batteries, and providing electrical insulation is associated with electrical insulating materials rather than transformers themselves.