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The way the circuit is drawn is super confusing to me

  1. Jun 2, 2013 #1
    1. The problem statement, all variables and given/known data

    I have no idea how to start this problem the way the circuit is drawn is super confusing to me.

    My original thought would be the two 6's are parallel but that is not true.

    What method should I use?

    I am more comfortable with voltage nodal/ mesh.



    9u6kp3.png



    2. Relevant equations



    3. The attempt at a solution
     
  2. jcsd
  3. Jun 2, 2013 #2

    lewando

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    Two (or more) of the resistors are in parallel.
     
    Last edited: Jun 2, 2013
  4. Jun 2, 2013 #3
    I manipulated it in pspice and found that the 6 and 3 are in parallel. Would it be incorrect to then do mesh method, but keeping requivilent?
     
  5. Jun 2, 2013 #4

    lewando

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    There is an additional pair of resistors that are in parallel that can further simplify the circuit. Redraw the circuit differently to see it better. Mesh method is fine. Note that I1 becomes "hidden" as a result of the "further simplification", but is easily recoverable.
     
  6. Jun 2, 2013 #5
    I think I got it. The 6 parallel with the 3 which gives a req=2 then the req is parallel with 3, after that it becomes simple.
     
  7. Jun 2, 2013 #6

    lewando

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    I'm not sure you are stating it correctly. Please, if you can, attach a picture to be clear.
     
  8. Jun 2, 2013 #7
    2f0dug4.png

    This is what I mean first step I rewrote the circuit,

    second step I simplified 6 and 3 which gave me req=2.

    Then I simplified 2 and 3 which gave me requ=6/5
     
  9. Jun 2, 2013 #8

    lewando

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    In your first step, when you repositioned the 6Ω from the top to the bottom you disconnected it and attached it to the bottom of the nonexistent current source (the line segment in parallel with the 3Ω).

    Try drawing this in a "ladder" style--identify your nodes, placing the bottommost on the bottom, the topmost (pick the one that makes most sense) on the top, and middle node(s) in the middle.
     
  10. Jun 2, 2013 #9
    2zf3ga0.png

    Like this?
     
  11. Jun 2, 2013 #10

    lewando

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    More like this (attached).
     

    Attached Files:

  12. Jun 2, 2013 #11
    Hmm by that picture it seems like it simplifies completely. Is that the case?
     
  13. Jun 2, 2013 #12

    lewando

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    Same circuit, just unwound a bit. At maximum reduction I1 disappears. You are going to have to deal with that twist.
     
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