Faraday's Law

Any change in the magnetic environment of a coil of wire will cause a voltage (emf) to be "induced" in the coil. No matter how the change is produced, the voltage will be generated. The change could be produced by changing the magnetic field strength, moving a magnet toward or away from the coil, moving the coil into or out of the magnetic field, rotating the coil relative to the magnet, etc.

                                                       FURTHER EXPLANATION

Faraday's law is a fundamental relationship which comes from MAXWELL EQUATION. It serves as a succinct summary of the ways a voltage (or emf) may be generated by a changing magnetic environment. The induced emf in a coil is equal to the negative of the rate of change of MAGNATIC FLUX times the number of turns in the coil. It involves the interaction of charge with magnetic field.