General solution to the circuits

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killingb
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assuming that the circuit will lead to infinite, but converging, and R1,R3,R5 are in increasing magnitude, R2 is constant, is there a general formula for this problem?
 
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  • Hand-drawn infinite ladder circuit: series resistors R1, R3, R4, R5 along the top, with shunt resistors R2 hanging down from each junction, currents I0 to I4 labelled, extending to infinity on the right. Note reads R2 is resistance of solution and R1, R3, R4, R5 are resistance of Cu, with R1 < R3 < R4 < R5.
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Not that I could help you with your question anyhow, but it might be a good idea for you to re-post your diagram. I can't even see the lettering on it.
 
The equivalent resistance of the ladder network is [tex]R_2[/tex] in parallel with the rest of the ladder (from [tex]R_1[/tex] to infinity).
If I understood it well, [tex]R_2[/tex] is the solution. For the resistance of a parallel connection to be equal to one of the resistances, the other one must be infinity.
 
My apologies, killingb... I didn't realize until now that the picture was enlargeable after opening. :redface:
 
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I'm not sure what the question is.

If you lable the left input as A B and the right output as C D.

Then the measured resistance A B will never be greater than R_2,1 or less than sqrt(R_2,1^2 + R_1^2).
The measured resistance at C D will never be > R_n + R_2,n or < R_n.
The measured current through R_2,n will approach 0.

Where does the infinity come from?