What phenomenon is induced by a change in a magnetic field?

The phenomenon induced by a change in a magnetic field is electromagnetic induction. This principle, discovered by Michael Faraday, explains how a changing magnetic field can produce an electric current in a conductor. The basis of this concept is that when the magnetic field around a coil of wire changes, it creates an electromotive force (EMF) that induces an electric current. This principle is foundational in many applications, such as the functioning of electric generators and transformers.

Other options, while they have their own contexts, do not relate directly to the process of a changing magnetic field inducing electrical current. Thermal induction pertains to heat transfer processes, mechanical induction would relate to physical force applications, and chemical induction involves changes in chemical reactions, none of which are concerned with the direct interaction of magnetic fields and electrical processes.