Help with this confusing circuit Using superposition find voltages

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Homework Help Overview

The discussion revolves around analyzing a circuit to find the voltages at points A, B, and C using the superposition principle. Participants are exploring the implications of circuit components and current flow in relation to this method.

Discussion Character

  • Exploratory, Assumption checking, Problem interpretation

Approaches and Questions Raised

  • Participants discuss the initial findings of current through certain resistors and suggest analyzing different parts of the circuit separately. Questions arise regarding the implications of having paths with different resistances and the flow of current through those paths.

Discussion Status

Some participants have offered hints and suggestions for analysis, including the use of Kirchhoff's Current Law (KCL) and Kirchhoff's Voltage Law (KVL). There is an ongoing exploration of the circuit's behavior, particularly concerning the flow of current and the impact of resistance in different paths.

Contextual Notes

Participants are navigating assumptions about current flow in the circuit, particularly regarding paths with zero resistance and the influence of voltage sources. There is a noted complexity in understanding how these factors interact within the given circuit setup.

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Help with this confusing circuit! Using superposition find voltages!

The problem is

"In the following circuit, find the voltages at A,B, and C. Use or confirm with superposition."

I was able to find the current through the top one ohm resistors as .333A (sorry didnt label on my picture). but what do i do next?


PICTURE:
http://imageshack.us/a/img689/7025/circuit3a.jpg
 
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You could try to analyze the lower part, and ignore the upper part for a while (as you know its contribution already). What is the current flowing through the resistor below B?
 
There is a little trick here. Actually the circuit is quite simple (in fact, as simple as a circuit can be).

Hint: If you have two paths in a circuit and one of them has o resistance, all charges will flow trough that path.
 
Vvs

It is very simple. Try using KCL and KVL.

For example:

I is flowing through the top resistor and 1A is flowing in the bottom left branch. Applying KCL at node A. I+1A will flow through the 1ohm resistor from Node A to Node B. Multiply that current by the 1 Ohm Resistor will give you the voltage drop across the 1ohm resistor so B=A-(I+1A)*1.

Continue analysis in a similar fashion for the rest of the circuit.

hope this helps
 
VVS said:
It is very simple. Try using KCL and KVL.

For example:

I is flowing through the top resistor and 1A is flowing in the bottom left branch. Applying KCL at node A. I+1A will flow through the 1ohm resistor from Node A to Node B. Multiply that current by the 1 Ohm Resistor will give you the voltage drop across the 1ohm resistor so B=A-(I+1A)*1.

Continue analysis in a similar fashion for the rest of the circuit.

hope this helps

What you say is usually ok, but not for this paticular problem. All the current will flow only trough the resistor at the top of the circuit. As for the bottom part, all the current will flow trough the resistance-free cable.
 
CFede said:
There is a little trick here. Actually the circuit is quite simple (in fact, as simple as a circuit can be).

Hint: If you have two paths in a circuit and one of them has o resistance, all charges will flow trough that path.

sorry I do not understand. Which two paths and which has 0 resistance?
 
CFede said:
What you say is usually ok, but not for this paticular problem. All the current will flow only trough the resistor at the top of the circuit. As for the bottom part, all the current will flow trough the resistance-free cable.
Did you check the direction of the 1A source to the left?
There will be a current flow in the interior of the circuit.
 

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