Items used for induction experiments.
© Royal Institution / Science & Society Picture Library
Electromagnetic induction is the use of magnets to produce electric current. In 1831, Michael Faraday (1791-1867) had shown that moving one pole of a bar magnet into or out of a long coil of wire produced a pulse of electric current in the coil. Later, he rotated a copper disc between the poles of a powerful permanent magnet, and showed that a continuous current would flow in a wire connecting the centre of the disc to the edge of the disc.