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Induce e.m.f

  1. Apr 6, 2008 #1
    1. Is it induce e.m.f is a force?
    2. What is the eddy current?
  2. jcsd
  3. Apr 6, 2008 #2
    I'm sorry but these questions are poory phrased. The way you have used the terms really don't make any sense. I'm assuming English isn't your first language.

    Anyway I will attempt to answer the questions that I think you mean to ask. EMF, or Electromotive Force, is to all intents and purposes the voltage. It is a 'force' or 'potential difference' that causes circulation of current/electrons.

    An Eddy Current is something that is created in the magnetic iron used in transformers. It is basically a current that is caused within the magnetic core due to the windings. It causes energy losses as the currents cause the core to heat up. These are combated by making an iron core out of electrically insulated laminations of steel rather than a solid block.
  4. Apr 6, 2008 #3
    EMF is not a force, it is a voltage, or potential difference of the source.
  5. Apr 6, 2008 #4
    Although "emf" literally stands for "electromotive *force*", it is not really a force. In the early days of investigation into induction, the phrase was coined, as well as "mmf", which stands for "magnetomotive *force*", which also is not really a force in the true sense. Both emf and mmf are related to force.

    The emf quantity has units of "volts per turn", whereas mmf has units of "amp-turns". For a simple one turn or one loop circuit, emf is in volts, and mmf is in amps. The emf from point a to b is the total work done per unit charge transporting said charge from a to b along a specified path.

    Eddy currents are induced currents due to the presence of a time-varying magnetic field. If a ferromagnetic material has a time changing magnetic flux, induction takes place. Since ferromagnetic materials are also good conductors, the material itself conducts an induced current due to its own magnetic flux. Transformers, motors, and generators are examples of this phenomenon. Laminating the core into layers reduces the power loss associated with this property. Does this help? BR.
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