What is mutual induction?

Mutual induction refers to the process by which a change in electric current in one coil generates a voltage in another coil that is located in proximity to it. This is a fundamental principle used in transformers and inductors, where two coils are inductively linked. When the current in the first coil changes, it creates a changing magnetic field, which in turn induces a voltage in the second coil according to Faraday's law of electromagnetic induction.

This principle is essential in applications like transformers, where electrical energy is efficiently transferred between two circuits through mutual induction. The voltage induced in the second coil can be in the same or opposite direction depending on the direction of the current change in the first coil, illustrating the concept that coils can influence one another through their magnetic fields.

The other options describe different concepts. For instance, a coil inducing voltage into itself refers to self-induction, where a coil generates a voltage in response to its own changing current. The ability to isolate transformers pertains to their design and operational characteristics rather than to the principle of mutual induction itself. Lastly, creating high voltage from low voltage can occur in transformers but is a result of mutual induction in operation, not the definition of the phenomenon itself.