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Did I do my loop analysis correctly?

  1. Oct 1, 2011 #1
    1. The problem statement, all variables and given/known data


    2. Relevant equations

    3. The attempt at a solution

    If we were to call the bottom right loop I1, the top loop I2, and the bottom right loop I3. I got the following:

    I1 = 1mA
    I2 = 6mA
    I3 = 2mA

    Which gives me a final answer of I0 = -1mA.

    Is this correct?
  2. jcsd
  3. Oct 2, 2011 #2


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    Homework Helper
    Gold Member

    No, it is not correct.
  4. Oct 2, 2011 #3


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    Gold Member

    checking your answer is trivial. All the loop currents become immediately obvious once you assume you have I0, and then you can get the voltages across the resistors and when you add them up, you'll find that the voltage across the 20V source is not 20V, so clearly you have the wrong answer. Learn how to check you work. It's often just this simple.
  5. Oct 3, 2011 #4
    I fixed it and got:

    I1 = 3mA
    I2 = -1mA
    I3 = -1mA

    Which gives me a final answer of I0 = 4mA.
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