Solving Circuit with Large Resistor and Inductor: Q = CV?

AI Thread Summary
The discussion revolves around a circuit involving a large resistor, a capacitor, and an inductor, with the goal of finding an expression for the charge on the capacitor. The user proposes that there are two currents, I1 and I2, and suggests isolating the loop with I2 due to the high resistance of the first loop. They attempt to relate the charge Q to the voltage V using the formula Q = CV, while also considering the voltage across the inductor and resistor combination. However, confusion arises regarding the circuit diagram and the specific question being asked. Ultimately, the user decides to apply Kirchhoff's Laws to derive the necessary expressions for the circuit analysis.
bodensee9
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Homework Statement


Hello:

I've this circuit:
-----Resistor (100000 ohms)---/ (switch) -------
| | |A
Battery Capacitor Inductor
| | |
| | Resistor2
|_________________________|______________|B
At points A, B, they are connected to a oscilloscope. The inductor/resistor2 combination have an inductance of 0.01 henry. When the switch is closed, the oscillatorscope is triggered.

I think that you'd have 2 currents, I1 and I2, if I1 flows clockwise through the large resistor and then I2 flows counterclockwise through the second loop of the circuit. I think you can isolate the loop of I2 since resistance in the first loop resistor is so large (100000 ohms). So then I can just do C is approximately 1/w^2L, where L is the inductance and w is the angular frequency (which I am supposed to determine on a separate chart). But I am asked how I am supposed to find an expression for the charge on the capacitor? I know that Q = CV. So then V across this LResistor2 combination is the same as voltage across C.

Homework Equations


Q = CV
I = dQ/dt
V = LdI/dt + RI

The Attempt at a Solution


do I have:
V = \frac{dI_{2}}{dt} + R_{2}I_{2}, which is
Q/C=\frac{d^{2}Q}{dt^{2}} + R_{2}\frac{dQ}{dt}
and then
V = R_{1}I_{1} + Q/C?
Actually, not sure what to do about the rest? Thanks.
 
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Your circuit diagram did not come through in any way that can be interpreted. Also, it is not clear what you are asked to find.
 
Oh sorry, but never mind. I will just use old Kirchoff's Laws and write down the expression fot voltage across the 2 loops, and then derive the answer that way. Thanks anyway.
 
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