Solving RC Circuit Voltage: Find Vn

In summary, the problem is to find Vn in a circuit with capacitive voltage dividers and a load resistor in parallel with a capacitor. There are at least three different approaches to solving this problem, including using KVL and determining the Thevenin equivalent of the circuit. If V1 is an ideal source, then C1g is irrelevant and can be ignored in the analysis.
  • #1
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Homework Statement


Find Vn in the attached ckt.


Homework Equations





The Attempt at a Solution


C12 & C2G act as capacitive voltage dividers. But I don't know how to account for R in parallel with C2G.
 

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  • #2
There are at least three mathematically distinct approaches to solving this. What technique are you supposed to use?
 
  • #3
Antiphon said:
There are at least three mathematically distinct approaches to solving this. What technique are you supposed to use?

Any technique that works.
I'd prefer KVL.
 
  • #4
Anyone?
 
  • #5
If V1 is an ideal source, then C1g is irrelevant (except for the added current it will draw from the voltage source, it won't have any effect on the voltage delivered to the remainder of the circuit).

Why not remove the load resistor and determine the Thevenin equivalent of the rest? When you then add back the load you'll have a voltage supply and RC voltage divider to analyze (note that the Thevenin voltage will be frequency dependent unless V1 has a given fixed frequency).
 
  • #6
gneill said:
If V1 is an ideal source, then C1g is irrelevant (except for the added current it will draw from the voltage source, it won't have any effect on the voltage delivered to the remainder of the circuit).

Why not remove the load resistor and determine the Thevenin equivalent of the rest? When you then add back the load you'll have a voltage supply and RC voltage divider to analyze (note that the Thevenin voltage will be frequency dependent unless V1 has a given fixed frequency).
Thanks. I got it. It's so simple, if C1g is ignored.
 

1. What is an RC circuit?

An RC circuit is a circuit that contains both a resistor (R) and a capacitor (C). These components work together to store and release electrical energy, creating a time-varying voltage.

2. How do you solve for voltage in an RC circuit?

The voltage in an RC circuit can be found using the formula V = V0(1 - e-t/RC), where V0 is the initial voltage, t is the time, R is the resistance, and C is the capacitance. This formula is derived from the charge-discharge equation for a capacitor.

3. What is the time constant in an RC circuit?

The time constant in an RC circuit is the product of the resistance and capacitance (RC). It represents the time it takes for the voltage in the circuit to rise or fall to approximately 63.2% of its initial value.

4. What are some common applications of RC circuits?

RC circuits are commonly used in electronic devices such as filters, oscillators, and timing circuits. They are also used in audio equipment, power supplies, and communication systems.

5. How do you analyze an RC circuit using Kirchhoff's laws?

To analyze an RC circuit using Kirchhoff's laws, you can apply Kirchhoff's voltage law (KVL) and Kirchhoff's current law (KCL) to the different loops and junctions in the circuit. This will allow you to set up a system of equations that can be solved to find the voltage and current at different points in the circuit.

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