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Using Kirchoff's Rules

  1. Nov 15, 2012 #1
    My loop 1 equation is I1R1 + I2R2 + E1 = 0
    simplified to: 4I1 + 2I2 + 28 = 0
    Loop 2: I3R3 - E2 - I2R2 = 0
    simplified to: 1I3 - 7V - 2I2 = 0

    And my node 1 equation is: 0 = I1 + I2 + I3

    So doing algebra.. I get my I1 to equal 7.. which doesn't match with the -5A for I1 as given in the problem.

    Are my equations wrong? Or is my algebra wrong?
     

    Attached Files:

  2. jcsd
  3. Nov 15, 2012 #2

    lewando

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    Gold Member

    Loop 1 equation is wrong. No need to go further till that's fixed. I think you are trying to use the I references from the problem. Don't. Use only Iloop1 and Iloop2.
     
  4. Nov 15, 2012 #3
    Okay well I changed my node equation to I1 = I2 + I3 and got the right answer in the end.
     
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