Within a transformer, electromagnetic induction is the process through which:

Electromagnetic induction is a fundamental principle that describes how a fluctuating magnetic field can generate an electric current in a conductor. In the context of transformers, this process is essential for transferring electrical energy between two or more coils of wire without direct electrical contact. When alternating current flows through the primary coil, it creates a fluctuating magnetic field around it. This changing magnetic field then induces a current in the secondary coil placed within this magnetic field.

This principle is critical in the operation of transformers, which are designed to either step up (increase) or step down (decrease) voltage levels while maintaining power conservation. The induced current in the secondary coil depends on the rate of change of the magnetic field and the number of turns in the coils, exemplifying the significance of electromagnetic induction in electrical systems and transformers specifically.