Capacitor Charge and Voltage Distribution in a Circuit with Multiple Capacitors

AI Thread Summary
The discussion revolves around a circuit with three capacitors, where initially only C_1 is charged. After flipping the switch, the challenge is to determine the charge and voltage across C_2 and C_3, which are initially uncharged. The user calculates the equivalent capacitance of C_2 and C_3 as 12 uF and considers whether C_1's charge and voltage remain unchanged after the switch is flipped. There is uncertainty about C_1's influence on the other capacitors, with a suggestion that it may provide a brief current to C_2 and C_3 before stabilizing. The application of Kirchhoff's rules is recommended for analyzing the circuit after the switch is flipped.
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Homework Statement


http://img512.imageshack.us/img512/6864/59797183jd5.png

(capacitance in micro farads).

Initially the switch is at the left position and capacitors C_2 and C_3 are uncharged. Then the switch is flipped to the right position. Afterward, what are the chard on and the potential difference across each capacitor?

The Attempt at a Solution



First I turned C_2 and C_3 into a capacitor with equivalent capacitance 12 uF.

Before the switch flip, C_1 is charged to 100V and has 1.5 mC of charge. I'm not sure what happens after the switch flips though. Does C_1 still affect the circuit? If not, then its charge and voltage won't change from before it flipped. And then the voltage and charge on C_2 and C_3 are completely unaffected by the presence of C_1?
 
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Since the switch is flipped to the right, the circuit loop doesn't connect to both terminals of the battery, so what you could do is ignore the battery in the system. I'm thinking that C1 does affect the other 2 capacitors, in which it provides a current to the capacitors for a short interval of time. At some point, the current should approach 0 effectively enough and the capacitors should approach some steady charge and voltage. What you could use is Kirchoff's rules for the particular loop of C1, C2, and C3, in which you come up with an arbitrary current and set the net voltage along the loop to 0V.
 
Oh I didn't even notice that the battery wouldn't connect to the other two capacitors... doh!
 
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