Dielectric Compacitors Confirmation

[Trenthan]

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/C_eq) = (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 wouldn't 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
V_cap#1-3=Ed=(Q/Ae₀)*d

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 I am 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

 

[Trenthan]

ok i believe i am right or on the right track i found this website which helped a lot hopefully it is correct

http://dev.physicslab.org/Document....ctrostatics_DielectricsBeyondFundamentals.xml

if someone could just check site is reliable and correct than I've solved my own puzzle, its got some good example too** might help others

Cheers Trent

 

[baba89]

Thank you for your explanation, Trent. Your understanding of dielectric capacitors is correct. When multiple dielectrics are placed between two plates, the capacitance will decrease because the dielectrics act as insulators and decrease the electric field between the plates. This results in a decrease in the potential difference and therefore a decrease in capacitance. As you mentioned, arranging the dielectrics in series will also decrease the overall capacitance because the equivalent capacitance is lower than the individual capacitances. Therefore, if the goal is to have a high capacitance, using a single dielectric would be more effective. However, using multiple dielectrics can also have other benefits such as increasing the breakdown voltage or reducing the size of the capacitor. Overall, the choice of using one or multiple dielectrics depends on the specific requirements and design of the capacitor.