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Quick Answer. Michael Faraday discovered the law of electromagnetic induction in 1831. He realized that current in a circuit can be induced by changing the magnetic field. Faraday tested it by wrapping a paper cylinder with a wire and connecting the coil to a galvanometer. Faraday then moved the magnet back and forth inside the cylinder.
Faraday's experiment showing induction between coils of wire: The liquid battery (right) provides a current that flows through the small coil (A) , creating a magnetic field. When the coils are stationary, no current is induced. But when the small coil is moved in or out of the large coil (B) , the magnetic flux through the large coil changes, inducing a current which is detected by the galvanometer (G) .