Finding capacitance/dimensional analysis

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SUMMARY

The capacitance of two 2cm x 2cm square aluminum electrodes spaced 0.50 mm apart and connected to a 100 V battery can be calculated using the formula C = ε₀ * A / d. The area A is determined using A = 0.02 m x 0.02 m, resulting in an area of 0.0004 m². The calculated capacitance is on the order of 10^-12 farads, which corresponds to picofarads, confirming the accuracy of the calculation. Dimensional analysis shows that the units correctly simplify to farads, validating the approach taken.

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Two 2cm x 2cm square aluminum electrodes are spaced 0.50 mm apart. The electrodes are connected to a 100 V battery. What is the capacitance?



Ok, C = Q/V = epsilon_o*A / (d)

I used 0.02^2 for A (is that correct, or do I use the area of BOTH plates?), plugged in 0.00050m for d and the value for epsilon, and I got an answer that was on the order of 10^-12, and I know the answer is in picofarads, so that looked promising. However, when I did dimensional analysis, I couldn't make sense of the units I get from this calculation.

So, am I crunching the numbers correctly, and if so (and in any case), can someone clarify how the units work out? Thanks!
 
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[tex][\epsilon]= \frac{As}{Vm}; [A]=m^2; [d]=m; \frac{[\epsilon][A]}{[d]}=\frac{Asm^2}{Vm^2}=\frac{As}{V}=\frac{C}{V}=F[/tex]

All the variables inside square brackets [] denote the values, while all the variables outside the square brackets are the units (A=ampere, V=volt, m=meter, s=second, C=coulomb, F=farad)
 

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