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Homework Help: Kirchoff's Laws

  1. Jul 3, 2011 #1
    I have been teaching myself electronics from "Fundamentals of Electric Circuits". Can somebody help me with the attached problem? I know the answer, as it is given in the back of the book. However the method used to arrive at the answer eludes me. The answer is -4.444V and 98.75W. I have been able to figure out subsequent problems but this one has me stumped.
    I get the following equation for V0 -> V0/4=(10+2V0)
     

    Attached Files:

  2. jcsd
  3. Jul 3, 2011 #2
    Check the definition of V0 on the diagram. It's not what you wrote in the equation.
     
  4. Jul 3, 2011 #3
    Yea, check your signs. Current goes through a resistor from high to low voltage, your equation has charges gaining energy from the resistor.
     
  5. Jul 5, 2011 #4
    Thanks guys.
     
  6. Jul 5, 2011 #5
    the picture is very confusing, what is the diamond voltage??
     
  7. Jul 5, 2011 #6
    The diamond voltage is not necessary to figure out v0. The correct equation for v0 is v0/4=-10-2v0.
     
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