Charge on Capacitors in Series After Switch Flipped

AI Thread Summary
In a series circuit with two capacitors and a resistor, the initial charge on the first capacitor (C_1) is Q_0, while the second capacitor (C_2) starts uncharged. When the switch is flipped at t=0, the charge on C_1 decreases over time, while the charge on C_2 increases. The charge on C_1 is described by an exponential decay function, but the charge on C_2 must approach a constant value rather than zero as time progresses. The voltage drop across C_2 can be calculated using the equation Q=CV(1-e^{-t/τ}), where τ is the time constant of the circuit. Understanding the correct configuration and relationships between the components is crucial for accurate calculations.
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A capacitor, a resistor, and another capacitor is connected in series. The first capacitor, C_1, has an initial charge of Q_0, and C_2 is initially uncharged. The switch is flipped at t=0, what is the charge on each capacitor as a function of time?

So I thought
<br /> Q_1 = Q_{0}e^{-t(C_{1}+C_{2})/RC_{1}C_{2}}<br />

<br /> V_1 = Q_{0}e^{-t(C_{1}+C_{2})/RC_{1}C_{2}}/C_{1}<br />

<br /> Q_2 = C_{2}/C_{1}(Q_{0}e^{-t(C_{1}+C_{2})/RC_{1}C_{2}})(1-e^{-t(C_{1}+C_{2})/RC_{1}C_{2}})<br />
but this is apparently wrong

where am I messing up?
thanks.
 
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Is the configuration ---C1----R---C2 ---- ?

as opposed to


Vin-----C1---+---C2--- Vout
|
R
|
----------+---------​

The charge diminishes on C1, but increases on C2, so the solution cannot be exp(-At), which would go to zero at t = infinity. The solution must go to some constant, and the charge would be partitioned according to the relative capacitances.
 
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this is the diagram given
http://www.columbia.edu/~kqc2101/circuit.gif

so for Q_2 what would be the voltage drop V that charges C_2 in the equation
<br /> Q=CV(1-e^{-t/\tau})<br />
?
 
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