Help with this confusing circuit Using superposition find voltages

AI Thread Summary
The discussion focuses on solving a circuit problem using superposition to find voltages at points A, B, and C. Participants suggest analyzing the circuit by applying Kirchhoff's Current Law (KCL) and Kirchhoff's Voltage Law (KVL) to determine current flow and voltage drops. A key insight is that if one path in the circuit has zero resistance, all current will flow through that path, simplifying the analysis. There is some confusion regarding the current direction and the contribution of different circuit components. Overall, the circuit is described as simpler than it initially appears, with emphasis on careful application of circuit laws.
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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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