Finding capacitance/dimensional analysis

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The capacitance of two 2cm x 2cm 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 should be calculated using the dimensions of one electrode, resulting in A = 0.02 m x 0.02 m. The calculated capacitance is expected to be on the order of picofarads, which aligns with the anticipated results. Dimensional analysis confirms that the units work out correctly, as the final units simplify to farads. The discussion emphasizes the importance of understanding both the calculation and the unit conversions in capacitance problems.
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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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[\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

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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