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Homework Help: Using Kirchhoff's Laws to find current in a circuit

  1. Nov 2, 2005 #1
    I have attached a picture of a circuit. I am trying to find the values of I1, I2, and I3. What I have come up with so far, using Kirchhoff's Voltage and Junction Laws is:
    I2=I1+I3
    for the left loop:
    9V - (5 ohms)I1 -4V - (10 ohms)I2 = 0
    which simplifies to:
    1V - (1 ohm)I1 - (2 ohms)I2 = 0
    for the right loop:
    14V - (10 ohms)I3 -4V - (10 ohms)I2 = 0
    which simplifies to:
    1V - (1 ohm)I3 - (1 ohm)I2 = 0
    I am pretty certain that I have these correct, but I can't seem to solve my system of equations--whenever I try to add or subtract the equations, several terms cancel, leaving me with a current equaling zero.
    I would really appreciate some help. Thank you. :!!)
     

    Attached Files:

  2. jcsd
  3. Nov 3, 2005 #2

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    Answered in "introductory Physics" forum.
     
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