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Classical Hall effect when current has neutral charge

  1. Mar 17, 2015 #1
    If i have a current of both negative and positive charges(i know that there is also current from only negative and only positive charges,i'm not confused) along an infinite wire of square cross-section,and the we put a homogeneous magnetic field normal to the current,then a Lorentz force acts on both the positive and negative charges and it is in the same direction for both of them(negative charges move in the opposite direction of the positive charges so from the equation of the Lorentz force,the negative sign from the negative charge and the negative sign from the velocity vector cancel each other out-considering positive velocity vector in the direction that the positive charges are moving).But because the forces act in the same direction AND because negative and positive charges attract each other,then we will have accumulation of both negative AND positive charges on near the one end of the wire.So,the question is,will there be a potential difference transverse of the wire like the normal classical Hall effect?
  2. jcsd
  3. Mar 18, 2015 #2


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    Then they will cancel and you will have no current.
  4. Mar 18, 2015 #3
    no,this is not the case.the overall charge will be zero but there will be current.one in one direction and one in another(check it out in books)
  5. May 9, 2015 #4
    You're assuming the wire to have an infinite length so how can the wire have ends?
  6. May 9, 2015 #5

    jim hardy

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    seems to me
    one amp of 'Technician's current' , negative charge moving left to right
    one amp of 'Engineer's current' , positive charge moving right to left
    adds to
    two amps of either observer's current moving in whichever direction they believe current to flow.

    Did i mis-read the question ?
  7. May 9, 2015 #6


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    The negative “electron” current flows one way, while the positive “hole” current flows the other way.
    That is really only one classical “current”, but what is it's magnitude and polarity. {-2, -1, 0, 1 or 2} ?

    See; http://en.wikipedia.org/wiki/Hall_effect#Theory My bold.
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