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Basic principle of electrostatics?

  1. Jun 18, 2010 #1
    I seem to be having trouble grasping a very basic principle in electromagnetism. I have been told, in numerous places, that the electric field inside a conductor is zero. (Electrostatics). Yet I keep coming across problems in the textbook like this one:

    "Use Gauss's Law to find the electric field inside a uniformly charged sphere (charge density 'ro')."

    where for Q[enclosed] = charge density * volume

    However, don't all the charges move to the surface of the sphere? and the electric field IN the sphere is subsequently zero?
  2. jcsd
  3. Jun 18, 2010 #2
    uniformly charged sphere =/= conductor in all cases.
  4. Jun 19, 2010 #3
    Yes this is true so long as there is not current flowing - all charges are stationary.

    As soon as a current flows there is a field.
  5. Jun 19, 2010 #4


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    The OP did indicate that this is Electrostatics. So there is no need to make such qualification.

    Feldoh has sufficiently answered the question here, that just because one has a spherical charge, it doesn't mean that one also has a conducting sphere.

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