RC Circuit Problem: Find I1, I2, I3 and Q

AI Thread Summary
The discussion revolves around solving an RC circuit problem involving three resistors and a capacitor after the switch has been closed long enough for the capacitor to charge fully. The key points include the need to apply the voltage divider rule to determine the steady-state currents I1, I2, and I3, rather than assuming all voltage drops across the first resistor. The voltage across the capacitor in steady state is crucial for calculating the charge on it. Participants emphasize the importance of understanding the circuit configuration to correctly apply Ohm's law and the voltage divider principle. Accurate calculations for the currents and capacitor charge are essential for solving the problem.
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Homework Statement



In Figure P18.50, suppose that the switch has been closed for a length of time sufficiently long enough for the capacitor to become fully charged. (R = 12.0 k, R2 = 17.0 k, R3 = 1.00 k, V = 9.70 V)

The picture is under attachment

a) Find the steady-state current in each resistor.
I1 = µA?
I2 = µA?
I3 = µA ?

(b) Find the charge on the capacitor.
µC ?


Homework Equations



R = V / I

q = Q e^(-t/RC)

The Attempt at a Solution



Well, since after the switch is closed, I figured all 9.7 V goes to the first resistor, so I used R = V / I to get the current for the first one. But it's wrong.
 

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It's wrong because there is a voltage divider formed with one of the other two resistors in the steady state. Which one? In the steady state, what is the voltage across the capacitor?
 

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