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Homework Help: Kirchoff's Rule - circuit with 3 batteries

  1. Aug 27, 2008 #1
    1. The problem statement, all variables and given/known data
    Hello everyone

    I need to find the current through the 22 ohm resistor. I've tried to solve this problem for many hours now... I can't find what I'm doing wrong! Please find a rough diagram attached.


    2. Relevant equations
    Kirchoffs rules


    3. The attempt at a solution
    I1 + I2 = I3

    top loop:

    -8 -22I1+12-14I3 = 0
    0.286 - 1.57I1 = I3

    perimeter loop:
    -8 -22I1 +12 I2 -18 =0
    2.17 +1.83 I1 = I2

    Inputting these numbers into the first equation:
    I1+I2=I3
    I1 +2.17 +1.83I1 = 0.286-1.57I1
    I1 = -0.428A

    I then put the I1 into the loop equations and found:
    I2= 1.39 A
    I3= 0.958 A

    However, when I'm trying to find the voltage across the points A and B, these currents do not yield consistent voltage drops across the three portions of the circuit.

    I really appreciate any help!
     

    Attached Files:

  2. jcsd
  3. Aug 27, 2008 #2
    Sorry- i actually think this is correct. There goes a couple hours!
     
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