Capacitance Circuit - Voltage and Charge

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SUMMARY

The discussion focuses on calculating the equivalent capacitance, charge, and voltage across capacitors in a circuit. The equivalent capacitance was determined to be 0.012 microfarads using series and parallel capacitance rules. For the charge on each capacitor, the calculations yielded 1 microcoulomb for C2 and 2 microcoulombs for both C1 and C3 when a 100V battery is connected. The participant initially struggled with the voltage calculations but resolved the issue by recognizing the need to use the combined capacitance for capacitors in parallel.

PREREQUISITES
  • Understanding of capacitance and the formula C=Q/V
  • Knowledge of series and parallel capacitance rules
  • Familiarity with microfarads and microcoulombs as units of measurement
  • Basic circuit analysis skills
NEXT STEPS
  • Study the principles of series and parallel capacitor combinations
  • Learn about the impact of voltage on charge distribution in capacitors
  • Explore advanced capacitor circuit analysis techniques
  • Review practical applications of capacitance in electronic circuits
USEFUL FOR

Electrical engineering students, circuit designers, and anyone involved in analyzing or designing capacitor circuits will benefit from this discussion.

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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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