Pulling apart a charged capacitor and Poynting theorem.

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Spinnor
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Suppose we have equal and opposite charge densities on a parallel plate capacitor. Let the plates be separated some small distance d (small when compared with the plate size). Now slowly separate the plates so that their separation is now doubled to 2d. We have done work and the electrostatic field energy has roughly doubled. Should a careful application of Poynting's theorem to this problem account for the doubling of electrostatic energy?

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Spinnor said:
We have done work and the electrostatic field energy has roughly doubled. Should a careful application of Poynting's theorem to this problem account for the doubling of electrostatic energy?
Yes.
 
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