Transformers work on which of the following principles?

Transformers operate based on Faraday's Law of Electromagnetic Induction, which states that a changing magnetic field within a coil of wire induces an electromotive force (EMF) across that coil. This principle is vital for the functioning of transformers, as they rely on alternating current (AC) to produce a magnetic field that fluctuates over time. As the current changes, it generates a varying magnetic field that induces voltage in another coil of wire, thus allowing the transformer to step up or step down voltages.

While Lenz's Law describes the direction of induced current as opposing the change that created it, it is not the primary principle governing the action of a transformer. Similarly, Ampere's Law pertains to the magnetic fields generated by electric currents, and Fleming's Law, which includes Left-Hand and Right-Hand rules, is used to determine the direction of force in electric motors and generators, not transformers. Understanding these principles highlights why Faraday's Law is the foundational concept in transformer operation, making it the most relevant choice in this context.