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Resistance of a capacitor

  1. Feb 16, 2015 #1

    Please I would like to know how the resistance of the plates of a capacitors work? Is it the same as a resistor?
    If yes, is there electric field like inside a resistor?

    Thank you
  2. jcsd
  3. Feb 16, 2015 #2
    Hi Starter, from a 50,000 foot level, an ideal capacitor has no internal resistance. Are you really asking about a model with only a series resistance with the capacitor or the model that contains a series resistor with the capacitor and parallel leakage resistance?

    Electronic devices have different approximations depending on their application. Depending on the application (design) of the circuit governs which approximation is required. Some applications can use the ideal approximation, but if certain circuit requirements such as high frequency operation, could make it important to consider a non ideal case. A good place to learn more about these effects is a book on network analysis. There they will discuss this in detail and how it relates to first, second, etc
    order circuits usually expressed and solved using Laplace transforms since solving the differential equations are easier to solve this way.

    The addition of the series resistor case adds a simple RC time constant to the circuit connected to the capacitor.

    The parallel resistance represents the leakage resistance. This value is usually much larger than the circuit elements the capacitor is connected to and can in most cases can be ignored. I hope keeping the response simple is helpful
  4. Feb 16, 2015 #3
    Im talking about the resistance of capacitor's plates
  5. Feb 16, 2015 #4
    The resistance of the capacitor plates act like all other kinds of resistance; it reduces current. However, the charges are more driven to reach the other plate than moving around in the plate. There is an electric field present when there are charges on the plates.
  6. Feb 16, 2015 #5
    Are you trying to make an analogy between the electric field generated in a resistor as compared to that in a capacitor? I have checked back through my college text books, and "plate resistance" is not a topic discussed in my books. I have never used it as a design factor or parameter in circuit analysis. Not sure if I understand what you are really asking, sorry.
  7. Feb 16, 2015 #6

    I think nDenver has the best and clearest answer. This is where I was heading in terms of a response
    Last edited by a moderator: Mar 3, 2016
  8. Feb 16, 2015 #7
    sorry for the mispelling
  9. Feb 16, 2015 #8
    But the resistor has an electric field inside it but for example internal resistance inside an EMF is different however it resists the movements of electrons. That's why I am asking about the resistance of capacitor's plate
  10. Feb 16, 2015 #9
    I am talking about resistance of capacitor's plate and related Equivalent Series Resistor due to its conductivity
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