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Magnet and coil producing electric concept?

  1. Dec 6, 2008 #1
    I would like to know..what is the concept of rotating a magnet above a coil of wires to produce electricity.. what is the factor affects the power of electricity produce..

    1)Is it the number of coil?
    2)is it the power of magnet?
    3)is it the distance between magnet and coil
    4)or anything else..

    can u help me with explaining the concept to me.i am trying to produce electricity by using kinetic energy from the wind turbine i construct...on the shaft..i attach the magnet and beneath it i put the coil...when the turbine is rotating,the shaft will rotate and subsequently the magnet will rotate above the coil..

    so can anyone plz suggest n help me explaining about the concept..
    thank you.
  2. jcsd
  3. Dec 6, 2008 #2


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    Gold Member

    It's a function of 2) and 3). I believe 1) only affects the voltage (and current of course).


    I'd say strength for 2) instead of power, though.
    Last edited: Dec 6, 2008
  4. Dec 7, 2008 #3
    1. If a conductor moves or ‘cuts’ through a magnetic field, voltage will be induced between the terminals of the conductor at which the magnitude of the induced voltage is dependent upon the velocity of the wire assuming that the magnetic field is constant. This can be summarised in terms of formulation as shown:
    eind = (v x B) l
    v – velocity of the wire
    B – magnetic field density
    l – length of the wire in the magnetic field

    2. The value of l (length) is dependent upon the angle at which the wire cuts through the magnetic field. Hence a more complete formula will be as follows:

    eind = (v x B)l cosθ

    θ - angle between the conductor and the direction of (v x B)

    3. The induction of voltages in a wire moving in a magnetic field is fundamental to the operation of all types of generators.

    4. Power production is related to prim over mechanical system and electromagnetic system is suitable media for energy conversion. Therefore if you don't use suitable above mentioned parameters (v,B,l,θ), the energy losses increase in duty of energy conversion.

    Creative thinking is enjoyable, Then think about your surrounding things and other thought products. http://electrical-riddles.com
  5. Dec 13, 2008 #4
    My studies have led me to understand that, the incident angle needs to be considered as well. If you approach your magnet and the wires are not at right angles(tangental) to it the weaker an induced electromotive force is realized. Just to clarify, if you run your wire relative to the magnet and the relative positions are in parallel, you will not realize a force at all.

    Hope that helps
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