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Homework Help: Multiloop Circuit Total Resistance

  1. Mar 30, 2008 #1
    Hey guys, I have a quick multiloop circuit question:

    You're given this circuit with each of the resistors being 5 ohms and are asked to find the total resistance between points F and G.


    I imagined a 15V battery between those two points so I could get currents.

    - Through the top loop from F to G I get 1A.
    - Through the middle resistor and down through the bottom right resistor again I get 1.5A.
    - Through the bottom left resistor I get 2A.

    I (wrongly) conclude that the total current is 5.5A, then 15/5.5 = 2.72... -- not the right answer.

    Any help would be much appreciated.

    Much obliged,
  2. jcsd
  3. Mar 30, 2008 #2
    And by 2A for the bottom resistor I mean 3A. Sorry for the double post.

    Thanks again.
    - Steve.
  4. Mar 30, 2008 #3
    To help describe I am going to name your resistors beginning at F, R1 R2 R3 R4 moving clockwise. R5 is in the center. Combine R1 and R2 in series to act as one resistor in parallel with R5. Then consider R1,R2,R5 as one resistor in series with R3. Finally R4 in parallel with the value you calculated as equivalent to the other 4 resistors.
  5. Mar 30, 2008 #4
    Thanks, I was getting a little Kirchhoffed out there I think. But problem solved!

    Much appreciated!
  6. Mar 30, 2008 #5
    Oh yeah, Jerkhoffs law; I have forgotten it completely ;)
  7. Jun 2, 2009 #6
    how to find the equivalent resistance if there would have been one more resistance like R5 from the point G .
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