Electrodynamic Charge Transfer

Discussion in 'Physics' started by Senior777, Mar 13, 2014.

  1. Senior777

    Thread Starter New Member

    Mar 6, 2014
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    This is to briefly present and discuss a (new?) effect of charge-transfer (charge separation) with some potential applications as predictable from Relativistic Electrodynamics, hoping to get your comments. (The effect has some similarities with homopolar induction but is essentially different, as will be shown.)


    Relativistic Electrodynamics revealed that the Lorentz-Formula for electromagnetic induction E = v X B - pertaining to the electric field strength E acting on a charge crossing a magnetic field B with relative velocity v - can be deduced from the more fundamental laws of Special Relativity.



    Imagine a grounded stationary superconducting circuit carrying dc-current I with a straight wire section and an observer moving with velocity v parallel to that wire. This observer will simultaneously notice the magnetic field B surrounding the wire (which also exists in the laboratory rest frame) and an electrostatic field E= v X B inexistent in the laboratory rest frame, apparently emerging from that wire. However, the source of this electro*static field is not deducible from the Lorentz-Formula. Moreover, Maxwell’s field equations require that an electrostatic field E can only emerge from charges acting as sources of electrostatic flux. Hence also the electric field E = v X B must emerge from electrostatic charges located in the wire. With respect to the conservation of charge rule the required charging of the previously electrically neutral wire can only result from a disparity among the charge-densities of negative electrons and stationa*ry positive atomic nuclei in the wire. This apparent charge disparity has been shown to be a “pure” relativistic effect which may be called “Differential Lorentz Contraction” referring to the different variation of densities of the drifting conduction electrons and the statio*nary atomic nuclei, when observed from a moving frame of reference. Essentially, the charge-disparity in the wire is proportional to the current I and the relative velocity v of the observer. (The precise derivation of this charge disparity can be extracted from textbooks dealing with Special Relativity or Relativistic Electrodynamics. (See e.g. R. Feynman “Lectures on Physics “ 2, Ch. 13-6.) The most comprehensive analysis is based on relativistic “4-potential” and “4-current” vector transformations.



    With reference to the above observations the following 3 “thought-experiments” and questions can be formulated :


    a) a) If the moving observer lets a small piece of (otherwise isolated) metal slide over the wire: Will that sliding piece of metal acquire the same (apparent) electrostatic potential as the wire and become electrostatically charged?


    b) b) If the moving piece of metal is detached from the wire without change of velocity: Will that piece of metal retain the a.m. charge if it remains electrically isolated?


    c) c) If that piece of metal is decelerated and stopped to rest in the laboratory frame: Will it conserve its a.m. charge?


    Remark 1:
    Electric charge is a relativistically invariant quantity being conserved during any acceleration or deceleration process. Hence it can be expected that if the first answer is “yes”, all further answers should also be “yes”.


    Remark 2:
    The a.m. piece of metal also is subjected to homopolar induction, which however only superimposes an electric dipole moment without affecting its total charge.

     
  2. studiot

    AAC Fanatic!

    Nov 9, 2007
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    Unfortunately you seem to misunderstand the Lorenz Force. It is a mechanical force not an EMF as you have stated. Simple dimensional analysis of your equation should tell you this.

    I suggest you start by getting your basic theory in shape first.

    Here is an introduction pitched at a reasonable level, including some relativistic efffects.

    http://www.angelfire.com/sc3/elmag/files/EM02LE.pdf
     
    Last edited: Mar 13, 2014
  3. Senior777

    Thread Starter New Member

    Mar 6, 2014
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    0
    Thank you for your quick response and your comments.
    However having read your recommended paper I couldn't find the point I wanted to address. The theory to which my question is related is most conveniently presented in: Here


    Best Regards,

    Senior777
     
  4. studiot

    AAC Fanatic!

    Nov 9, 2007
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    I'm sorry you didn't find what you wanted in our responses.

    However the fact remains that you did not understand something more basic than the much more advanced mathematics presented in your link.

    I still maintain it is most important to address this first, before moving on to the more advanced stuff.

    Everything in your link was presented at a more elementary level in mine, and additional your Lorenz misconception was also addressed.

    Do you now understand the difference between mechanical force and EMF?
     
    Last edited: Mar 30, 2014
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