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Homework Help: Circuit with Two Batteries and Six Resistors

  1. Feb 15, 2013 #1
    1. The problem statement, all variables and given/known data
    A circuit is constructed with six resistors and two batteries as shown. The battery voltages are V1 = 18.0 V and V2 = 12.0 V. The positive terminals are indicated with a + sign, The values for the resistors are: R1 = R5 = 64.0 Ω, R2 = R6 = 157.0 Ω R3 = 53.0 Ω, and R4 = 65.0 Ω. The positive directions for the currents I1, I2 and I3 are indicated by the directions of the arrows.

    https://www.smartphysics.com/Content/Media/Images/EM/10/h10_twoloop.png [Broken]

    2. Relevant equations

    KCL and KVL

    3. The attempt at a solution

    So i tried to make equations, but i'm not getting it to work out.
    Last edited by a moderator: May 6, 2017
  2. jcsd
  3. Feb 15, 2013 #2


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    It doesn't look like you have tried to simplify the circuit first?

    You could replace R2+R6 with an R7.

    Personally I think it's better to write the equation so the voltages sum to zero. I haven't checked if your equation is correct but I note that I6 = I2
  4. Feb 15, 2013 #3
    I summed them to zero initially, and then i moved them around so there weren't any negative signs. I also saw that I6=I2. I tried playing with that using I1+I3=I2 and I6+Iv(just assigned this to the v2)=I5(which i already solved from an earlier part)
  5. Feb 15, 2013 #4
    nvm, just figured it out
  6. Feb 15, 2013 #5
    thank you!
  7. Feb 15, 2013 #6
    are your origional equations correct?
  8. Feb 15, 2013 #7
    nah, i messed up one of the loops.
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