Does a Capacitor's Plate Resistance Work Like a Resistor's?

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SUMMARY

The discussion clarifies that an ideal capacitor has no internal resistance, but practical capacitors exhibit plate resistance that behaves similarly to resistors by reducing current. The conversation highlights the importance of considering both series resistance and parallel leakage resistance in circuit design, especially for high-frequency applications. The presence of an electric field is confirmed in both capacitors and resistors, although the mechanisms of charge movement differ. The concept of "plate resistance" is not commonly addressed in textbooks, indicating its limited relevance in standard circuit analysis.

PREREQUISITES
  • Understanding of capacitor fundamentals and behavior
  • Knowledge of series and parallel resistance in circuits
  • Familiarity with electric fields in electrical components
  • Basic concepts of network analysis and Laplace transforms
NEXT STEPS
  • Study the effects of Equivalent Series Resistance (ESR) in capacitors
  • Learn about the role of leakage resistance in capacitor performance
  • Explore network analysis techniques for circuit design
  • Investigate the differences between ideal and non-ideal capacitors in high-frequency applications
USEFUL FOR

Electrical engineers, circuit designers, and students studying electronics who seek to deepen their understanding of capacitor behavior and its implications in circuit design.

tonyjk
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Hello,

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
 
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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
 
Im talking about the resistance of capacitor's plates
 
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.
 
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 textbooks, 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.
 
Inventive said:
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 textbooks, 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.
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:
Inventive said:
I think nDenver has the best and clearest answer. This is where I was heading in terms of a response
sorry for the mispelling
 
nDever said:
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.

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
 
Inventive said:
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 textbooks, 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.
I am talking about resistance of capacitor's plate and related Equivalent Series Resistor due to its conductivity
 

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