Calculating Capacitance With Dielectric

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    Capacitance Dielectric
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Discussion Overview

The discussion revolves around calculating the capacitance of a capacitor with a dielectric material inserted between its plates. Participants explore different configurations and approaches to determine the new capacitance, considering factors such as the dimensions of the dielectric and its positioning relative to the capacitor plates.

Discussion Character

  • Technical explanation
  • Mathematical reasoning
  • Debate/contested

Main Points Raised

  • One participant presents a scenario involving a capacitor with plates of area A and a distance of 5m between them, questioning how to calculate the new capacitance when a dielectric of width 3m is inserted.
  • Another participant suggests treating the system as two capacitors—one with the dielectric and one without—and proposes using the series formula to find the total capacitance.
  • A different participant introduces a formula for capacitance involving the dielectric's width and constant K, but expresses confusion about whether the configuration changes if the dielectric does not touch the plates.
  • Another participant clarifies that if the dielectric is spaced off both plates, it can be modeled as three capacitors in series, emphasizing the importance of treating boundaries with an imaginary metal plate to simplify calculations.

Areas of Agreement / Disagreement

Participants present multiple competing views on how to approach the calculation of capacitance with dielectrics, and the discussion remains unresolved regarding the implications of the dielectric's positioning.

Contextual Notes

There are limitations regarding the assumptions made about the dielectric's placement and the implications of treating boundaries as separate capacitors, which are not fully explored in the discussion.

nishantve1
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Lets say There is a capacitor with the are of Plates A and the distance between the plates say is 5m if a dielectric of similar dimensions except the width is 3m is filled between the Capacitor plates how to calculate the new Capacitance ??
 
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Imagine a very thin metal plate at the boundary of the two dielectrics. Now you have two capacitors, one with the dielectric and one without. Simply calculate the value of the two capacitors and use the capacitors in series formula to arrive at your answer.
 


Okay so let's say the capacitor plates are at a distance d from each other and the inserted dielectric is of x width and constant K the formula comes out to be KAE0 /Kd-x(K-1) which solves the problem thanks ! What is confusing me is if the dielectric is displaced towards one direction that is it does not touch any of the plates will it still be considered as two capacitors ?
 


Okay, so the dielectric is spaced off both plates. Just imagine a very thin metal plate on both sides of the dielectric, now we have three capacitors, calculate each one then calculate the total value for those three capacitors in series. Bottom line is when you encounter a boundary, just imagine a metal plate there splitting the capacitor in two. So if you have a problem where different dielectrics are stacked just divide the problem into so many individual capacitors, then figure them in the series circuit.
 

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