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Homework Help: Dielectric Compacitors Confirmation

  1. Sep 10, 2008 #1
    Dielectric compacitors can contain 1 or multiple dielectrics, if we say have a capacitor with 3 dielectrics between the two plates. We can model it as 3 capacitors in series. Since we know that Capacitors in series the equivalent is

    (1/Ceq) = (1/C1)+(1/C2)+(1/C3)

    Wouldnt the overall capacitance be lower by having 3 dielectric between the two plates. If we separated the 3 into 3 seprate dielectric capacitors wouldnt the charge across all 3 remain constant Q0=Q1=Q2=Q3.

    Therefore the potential for each capacitor depends only on the width of the dielectric since

    Since A is constant all the same size, e0= 8.85*10-12, and Q is constant since they are in series. The potential depends only on "d" the width of the dielectric, thus capacitance C=Ae0/d, also only depends on the "d".

    Basically what im trying to say is if we have 3 individual capacitors, than arrange them in series the capacitance islower. Therefore if we want to build a capacitor with a high capacitance we only use a single dielectric since multiples decrease the capacitance of the capacitor due to the series arrangement of dielectric in the capacitor.

    Hope this is clear thanks Trent
  2. jcsd
  3. Sep 10, 2008 #2
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