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

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SUMMARY

The discussion focuses on analyzing a circuit containing a large resistor (100,000 ohms), a capacitor, and an inductor with an inductance of 0.01 henry. The user seeks to determine the charge on the capacitor using the formula Q = CV, while also considering the relationships between the currents I1 and I2 in the circuit. The user proposes using Kirchhoff's Laws to derive the voltage expressions across the loops to find the necessary parameters for their calculations.

PREREQUISITES
  • Understanding of Kirchhoff's Laws
  • Familiarity with capacitor and inductor behavior in circuits
  • Knowledge of differential equations in electrical circuits
  • Basic circuit analysis techniques
NEXT STEPS
  • Study the application of Kirchhoff's Laws in complex circuits
  • Learn about the relationship between charge, voltage, and current in capacitors and inductors
  • Explore the concept of angular frequency (ω) in RLC circuits
  • Review the derivation of voltage equations in series and parallel circuits
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Electrical engineering students, circuit designers, and anyone involved in analyzing RLC circuits and their dynamic behavior.

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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