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General solution to the circuits

  1. Jul 25, 2006 #1
    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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  3. Jul 25, 2006 #2


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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.
  4. Jul 25, 2006 #3


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    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.
  5. Jul 25, 2006 #4


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    My apologies, killingb... I didn't realize until now that the picture was enlargeable after opening. :redface:
    Last edited: Jul 26, 2006
  6. Jul 25, 2006 #5


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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 aproach 0.

    Where does the infinity come from?
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