Mesh current analysis

Discussion in 'Homework Help' started by jegues, Sep 23, 2010.

  1. jegues

    Thread Starter Well-Known Member

    Sep 13, 2010
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    The problem statement is to determine the values of the mesh currents of the circuit shown. See figure attached for my attempt and the circuit in question.

    Does anyone have any idea where I went wrong?

    I think I need to use the fact that i_{3} = 4i_{x}, and I can get i_{x} by using a KCL at node a.

    Any corrections on my work/suggestions/hints?

    Thanks again!


    EDIT: On a second attempt I obtained the following results,

    i1 = .328A

    i2 = -.609A

    i3 = -.438A

    Does that look any better?
     
    Last edited: Sep 23, 2010
  2. t_n_k

    AAC Fanatic!

    Mar 6, 2009
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    As an initial observation, it is clear that i1=ix so one would presume that i3=4*ix=4*i1

    So the results you have for i1 & i3 aren't consistent with that requirement.

    It would perhaps be worth your while to solve this by a purely nodal analysis approach and this may highlight where the error is arising.

    I have

    ix=i1=-0.375A.
     
  3. jegues

    Thread Starter Well-Known Member

    Sep 13, 2010
    735
    43
    Okay I tried solving it a 3rd time and I got i1 = -.292A

    I can't see what I'm doing wrong if anything.
     
  4. The Electrician

    AAC Fanatic!

    Oct 9, 2007
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    Why is it that in your edited post #1, you have a value of -.609A listed in the body of the post, but in the attachment you have I2 = -19/24 = -.7916667?

    The values I get are:

    I1 = -7/24 = -.2916667
    I2 = -19/24 = -.7916667
    I3 = -7/6 = -1.166667
     
  5. t_n_k

    AAC Fanatic!

    Mar 6, 2009
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    Agreed - my bad on that value of I1. Checked my working again - as attached. Mental math has gone off lately!
     
  6. jegues

    Thread Starter Well-Known Member

    Sep 13, 2010
    735
    43
    Okay thank you, I've got it now in my third attempt.

    The difference in values is from different attempts.

    First attempt on my figure, second in bold on my first post and on my third attempt I finally got it!

    Thanks again everyone!
     
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