Capacitance Circuit - Voltage and Charge

AI Thread Summary
The discussion focuses on calculating the equivalent capacitance and charge distribution in a circuit with capacitors. The equivalent capacitance was initially calculated as 0.012 microfarads, but there was confusion regarding the charge on each capacitor when a 100V battery is applied. The correct approach involves recognizing that capacitors C2 and C3 are in parallel, requiring the use of their combined capacitance for accurate charge calculations. After resolving the misunderstanding, the correct method was applied, leading to the realization that using the combined capacitance yields the correct voltage across each capacitor. The discussion highlights the importance of understanding capacitor configurations in circuit analysis.
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1. The Question
a. What is the equivalent capacitance of the combination shown in the figure ?
b. If a 100V battery is connected across the combination, what is the charge on each capacitor?
c. What is the voltage across each?
uggphysics.jpg


2. Equations
C=Q/V, adding capacitance rules

3. Solution attempt
For part a, I added C2 and C3 to get .03, then added the two in series (1/.02)+(1/.03) and took the inverse to get a combination capacitance of .012 microF

I am stuck on parts b and c, though. For B, we know Q=V/C and for C2 it would be Q=(100V)(0.01microfarads) which gives a charge of 1 microcoulomb.

for C3 it would be Q=(100V)(.02microfarads)=2 microcoulombs.
And for C1 it would be Q=(100V)(.02microF)= 2 microcoulombs.

However this answer is not working.

For part C, I tried plugging the charge and C into the same equation to get the V back out, but again this has not worked. I'm not sure if my units are off, or if I am missing something conceptually.[/b]

Any help would be appreciated!
 
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Nevermind, I just figured it out - I was trying to use the individual capacitance of C2 and C3 when I should have been using the combined since they are in parallel. :)
 
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