Page "Maxwell's equations" Paragraph 10

Faraday's law describes how a time varying magnetic field creates (" induces ") an electric field.

This aspect of electromagnetic induction is the operating principle behind many electric generators: for example, a rotating bar magnet creates a changing magnetic field, which in turn generates an electric field in a nearby wire.

( Note: there are two closely related equations which are called Faraday's law.

The form used in Maxwell's equations is always valid but more restrictive than that originally formulated by Michael Faraday.