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Homework Help: Transportation of Charges and Energy Lost

  1. Mar 2, 2008 #1
    1. The problem statement, all variables and given/known data

    http://img525.imageshack.us/img525/2069/spheressw9.jpg [Broken]

    At the initial picture, we have two spheres, such that,
    the first one has charge Q, and the second one has no charge.

    Then we connect these two spheres with a conducting wire and let some Q flow through the second sphere.

    For the initial energy, we have;

    Ei=Q[tex]^{2}[/tex]/{8*pi*epsilon*a)}

    For the final energy, after we did simple calculations, we have;

    Ef={Q[tex]^{2}[/tex]/(8*pi*epsilon)}*{1/(a+b)}

    And then, we find energy lost, such that,

    Ei-Ef={Q[tex]^{2}[/tex]/(8*pi*epsilon)}*{b/[a*(a+b)]}

    Then, we connected this energy lost to the resistance that the wire has.

    However, if we suppose the wire does not have a resistance, then, how can we explain the energy lost here?


    2. Relevant equations

    Energy:
    E=Q[tex]^{2}[/tex]/(8*pi*epsilon*r), where r is the radius of the sphere.

    Potential:
    V=Q/(4*pi*epsilon*r), where r is the radius of the sphere.


    Any comments will be appreciated.
     
    Last edited by a moderator: May 3, 2017
  2. jcsd
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