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Homework Help: Equivalent circuits resistor problem

  1. Sep 7, 2011 #1
    1. The problem statement, all variables and given/known data

    Find Req.

    2. Relevant equations

    Series: R1 + R2 + ...

    Parallel: 1/(1/R1 + 1/R2 + ...)

    3. The attempt at a solution

    There's no solution for this one in the book but I'm thinking that I can break this up into two parallel sets. Parallel1 = (R1*R4)/(R1 + R4) and Parallel2 = (R3*R2)/(R3 + R2). Is that correct?

    Attached Files:

    Last edited: Sep 7, 2011
  2. jcsd
  3. Sep 7, 2011 #2
    It's not exactly very easy figuring out that diagram, why not do it properly on paint and then upload the image?
  4. Sep 7, 2011 #3
    Yeah it didn't keep the white space. Sorry
  5. Sep 7, 2011 #4


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    Your parallel2 is correct.

    What is inbetween the right end of R4 and the bottom end of R1?
  6. Sep 7, 2011 #5
    The same voltage?
  7. Sep 7, 2011 #6
    Oh wait.. If I combine Parallel2 into the circuit as one unit it will now be in between the right end of R4 and the bottom end of R1.
  8. Sep 7, 2011 #7
    If you consider R1 and R4 in parallel, it has to be connected to the negative terminal right? What's helping completing the circuit?
  9. Sep 7, 2011 #8
  10. Sep 7, 2011 #9
    http://slimber.com/index.php?image=resistors.g80803 [Broken]

    See if that helps you visualize it better
    Last edited by a moderator: May 5, 2017
  11. Sep 7, 2011 #10
    Sort of.. If it was drawn like that then would the solution be:

    1/(1/R1 + 1/(R4 +R2) + 1/R3) ?
    Last edited by a moderator: May 5, 2017
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