What is Eddy Current?

Foucault in the year 1895 observed that when a mass of metal moves in a magnetic field or when the magnetic field through a stationary mass of metal is altered, induced current is produced in the metal. This induced current flows in the metal in the form of closed loops resembling ‘eddies’ or whirl pool. Hence this current is called eddy current. The direction of the eddy current is given by Lenz’s law.