What is the process of generating electric current from a changing magnetic field called?

The process of generating electric current from a changing magnetic field is known as electromagnetic induction. This phenomenon occurs when a conductor, such as a wire, is exposed to a changing magnetic field, which induces an electromotive force (EMF) within the conductor. This induced EMF causes a flow of electric current if the conductor forms a closed loop.

Electromagnetic induction is the principle behind various electrical devices, such as generators and transformers. For instance, in a generator, mechanical energy is used to rotate a coil within a magnetic field, leading to a change in magnetic flux and thus generating electric current.

Understanding electromagnetic induction is fundamental for many applications in electrical engineering and technology, as it is the basis for converting mechanical energy into electrical energy efficiently. Other options listed do not pertain directly to this process; for example, direct current generation refers to the creation of electric current that flows in one direction, while magnetic flux reversal and resonant frequency involve different concepts that do not involve the direct generation of current from changing magnetic fields.