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Homework Help: Concept question

  1. Feb 6, 2005 #1

    Suppose I have two balls that come into contact to make their charges say q1=q2. Would the charges be equal if the balls were of different size?

    I'd say yes, because mass is not relevant in Coulomb's law.
  2. jcsd
  3. Feb 6, 2005 #2

    Andrew Mason

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    If the balls are conductors, the charges on each ball will move until all charge is at the same electrical potential. Electrical potential on the surface of a conducting sphere is:

    [tex]V = \frac{Q}{4\pi\epsilon_0R}[/tex]

    If the balls are of different size (radius) but equal charge, the potentials will not be the same. So when they touch the charges will move so that the potential V for each is the same (ie. a sphere half the radius as the other, will have half the charge as the other).

    Last edited: Feb 6, 2005
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