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Electric Field Question

  1. Dec 17, 2012 #1
    For the equation ε=ΔV/r, does this work only between 2 parallel plates or would it work for point charges as well?
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  3. Dec 18, 2012 #2


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  4. Dec 18, 2012 #3
    I love Electrostatics <3
  5. Dec 18, 2012 #4


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    Do you know calculus? Your equation seems to be another way of writing [itex]|E| = \Delta V/\Delta r[/itex], which is only an approximation. The correct value is gotten by taking the limit as Delta goes to 0. Then you get:
    [itex]E=-\nabla V[/itex]
    In the special case of infinite parallel plate, they give the same answer, but for a curved E field you get a more accurate answer for smaller step size.
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