Eddy Current and Induced current --- Are they same?

Discussion in 'Physics' started by logearav, Jul 4, 2012.

  1. logearav

    Thread Starter Member

    Aug 19, 2011
    I want to know whether Eddy current and Induced Current are same?
    1)When flux linked with a circuit changes, an emf is induced in the circuit and this emf is called induced emf and the current is called induced current. The direction of current is given by Lenz law.
    2)Now, let me come to Eddy current. When we consider a metal plate oscillating between the poles of a magnetic field, an induced current is set up in the metal in the form of whirlpool and hence called Eddy current and this Eddy current sets up its own magnetic field opposite to the magnetic field of poles.
    The direction of induced current is given by Lenz law.
    So it makes me to think the induced current formulated by Faraday in Electromagnetic induction(1) and Eddy current(2) are same. Am i right , revered members?
  2. davebee

    Well-Known Member

    Oct 22, 2008
    An eddy is a fluid dynamics term that describes the swirling of liquids or gases, often in a whirlpool pattern. When an induced current has that circular pattern, it could be called an eddy current, as you noted.

    If the induced current is not circular, like when current is induced in a linear conductor such as a wire, then the phrase probably would not be used.

    But the phrase eddy current is a casual description, not a rigorously defined physics term, so your question does not have a rigorous answer; this is just my opinion.
  3. Markd77

    Senior Member

    Sep 7, 2009
    I'd say they are the same, it's probably better to picture concentric loops rather than a whirlpool. As you probably know, transformer and motor iron cores are laminated to reduce eddy currents.
    You can experience the magnetic field that they set up if you drop a magnet down a copper or aluminium tube or if you move a strong magnet over the surface of a chunk of aluminium like a heatsink.
  4. BillO

    Well-Known Member

    Nov 24, 2008
    In EM induction an eddy can be induced, but is not necessarily induced nor the only current induced, but they are the result of induction.

    So, how clear is that?

    Let me be more clear - the two terms are not analogous in all cases.