Solve Battery & Capacitors Network: Find C2,C3 PD & Q3 Charge

AI Thread Summary
The discussion focuses on solving a circuit problem involving a battery and capacitors, specifically determining the potential differences across C2 and C3, as well as the charge on C3 (Q3). Given that C2 is parallel to C3, the potential difference across both capacitors is the same. The energy stored in C2 allows for the calculation of its voltage using the formula W = 1/2 * CV^2. The total charge in the parallel configuration equals the charge on C1, and the charge on C2 can be calculated with Q2 = C2V2. Finally, Q3 is derived by subtracting Q2 from the total charge Q1.
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I have a circuit consisting of a battery and several capacitors, some quantities are known and some are not. The capacitors were completely uncharged before the battery was attached and we are considering the static situation. (Be sure to keep at least 3 sig. figs. in your answer for all parts of this problem.)

Given:
Q1: 7.9e-6
C1: 7.1e-6
C2: 1.9e-6
Energy stored on C2: W=5.6e-6 J
C2 is parallel to C3

I found:
the potiential distance across C1 is 1.126 V

I need to find:
-Potenital distance across C2
-Potential difference across C3
-The charge of Q3 on C3


Can you please help me? Thank you:)
 
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1) You know the relation
W=1/2 * CV^2
You can find V2 because you know C2 and W2

2) Since C2 and C3 are parallel V2=V3 (Pot. diff. across C2 and C3 are same)3) I assumed C1 is in series with C2 || C3. Q1 is known. Since they are in series total charge in C2||C3 is Q1. (In series connected capacitors the amount of charge stored in each capacitor is same). You can find charge in C2 using relation
Q2=C2V2.
From this Q3= Total charge in C2||C3 (ie., Q1) - Q2
 
Ok, thank you:)
 
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