Find the Equivalent Resistance in Complicated Electrical Circuits

AI Thread Summary
To find the equivalent resistance in complicated circuits, it's essential to identify which resistors are in series and which are in parallel. Labeling components and connection nodes in the circuit diagram aids in clarity and communication. Redrawing the circuit can help reveal relationships between resistors, making simplifications easier. A step-by-step approach involving single-step series or parallel simplifications can lead to the correct answer, which in this case is 3 ohms. This method encourages understanding and enables individuals to solve similar problems independently in the future.
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Hi! I have been trying to understand how a "complicated" circiut can be transformed to show which resistors are connected in series and which are parallel... Sometimes I manage to do it but it's often too hard for me because I can't find any sort of algorithm about it. Could anybody show me "step-by-step" how to transform this circuit for example...?
arx1303670379t.jpg

We need to find the equivalent resistance...
Thank you in advance!
 
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It's always a good idea to label the components in a diagram. In this case your resistors should be numbered R1, R2 etc. This allows people to identify what is being referred to and, if the OP doesit, doesn't waste 2 posts.
Alternatively you can label the connection nodes, A, B, C etc (which you have already started, but not finished).

I will comment (ask) if your diagram is correct since R1 and R2 are (almost) shorted out.

Can you see which resistors I mean by R1 and R2?

Oh and welcome to PF
 
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First of all, thank you for the very quick response... I have labeled the resistors... Now, how can I find the equivalent one.
P.S. The answer is 3 ohms.
jdv1303671601e.jpg
 
I find it often helpful to redraw the network to bring out the relationships. Sometimes you have to do this several times to get a clear result.

The attachment shows a sequence of single step series or parallel simplifications leading to the desired result.

Although I agree with the 3 ohm answer I have left you do do some of the work in the intermediate steps.

Hope this helps
 

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Well.. thank you once again! :) I hope now I can figure out HOW to do it myself...
 

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