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Homework Help: Two Spherical Capacitors - Pleas Help Friends!

  1. Feb 20, 2005 #1
    Hello Everybody, I am new to this site, However I have a quick question about the two spherical capacitors.

    Please take a look at this link here:

    http://online.physics.uiuc.edu/cgi/courses/shell/phys112/summer04/tmau.pl?04/05 [Broken]

    This is a problem about two spherical capacitors and I believe they are in series, If anyone could please help me out!

    If you need any more clarification please let me know!

    Thank You very Much!
    Last edited by a moderator: May 1, 2017
  2. jcsd
  3. Feb 20, 2005 #2


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    Homework Helper

    To calculate the capacitances, put a charge +Q on the inner sphere and -Q on the outer and find the voltage difference that results. Then C=Q/V, and this can be used in the usual way to get the answers to the second part.
  4. Feb 20, 2005 #3


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    Staff Emeritus
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    Gold Member

    What is you question? Please show us something of what you have done. Yes the caps are in series.
  5. Feb 20, 2005 #4
    Two Capacitors

    Hello all,

    I have the found the capacitance of the spheres by using

    (4*pi*Epsilon(0)*a*b)/(b-a) where a & b are in meters, for the first one and for the second capacitance i used the above formula and multiplied it by the k!

    All I need help is, is with finding the charge Q on the inner and and the outer surface, All I could possibly think about it is that it they are in series!

    Please Help!
  6. Feb 20, 2005 #5

    Doc Al

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    Staff: Mentor


    Two hints:
    In going around the circuit, what must the voltages add to?
    Since the inner conductors are connected, what must be their total charge?
  7. Apr 11, 2010 #6
    Is it actually possible? The inner shell wouldn't feel a thing of the outer applied voltage, would it? (being a conductor in electrostatic equilibrium)
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