Foucault’s current is also known as eddy current which are loops of electric current induced within conductors by changing magnetic field in conductor according to Faraday’s law of induction. When there is a discussion about eddy current first thing mentioned is that it flows in closed loop within the conductor in planes perpendicular to the magnetic field. According to Lenz’s law an eddy current creates a magnetic field that created it and then eddy current react back on the source of the magnetic field. If we take an example of a nearby conductive surface which will exert a drag force on a moving magnet that opposes its motion due to eddy current and this effect is employed in eddy current brakes which are mainly used to stop rotating power tools as quickly as they are turned off. The cause of eddy current involves energy loss in alternate current inductors, transformers, electric motors and some generators.
Properties of eddy current
Just like applications eddy current have properties which make clear its role and effect on conductors. As explained eddy current in conductors of none zero resistivity generates heat as well as electromagnetic force and these electromagnetic forces can be used for levitation, giving a strong braking effect and creating movements. There are many effects that eddy current has and that too undesirable effects for instance power loss in the transformer. Some of the self-induced eddy currents are responsible for the skin effect in the conductors. Eddy current consists of later and this latter can be used for non-destructive testing of various materials. Eddy current transforms some form of energy, for example, kinetic energy into heat and they can be minimized in these devices by selecting the magnetic core. It also mentioned that the conversion of input energy to heat is not undesirable but sometimes implies some practical applications.
What are the applications?
Applications play a very important role in the implications of these laws in a better way as eddy current use the drag force created by eddy current as a brake to slow and stop any moving objects as there is no contact with a brake shoe and there is no mechanical wear. It includes very strong handheld magnets that are made of neodymium so that one can easily observe a very similar effect by rapidly sweeping magnet over a coin which includes a very small separation. These are some of the applications which draw a fine line to great or destroy the law.