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I'm having trouble with this circuit problem - Power

  1. Mar 30, 2009 #1
    The homework problem is attached as a .jpg file and it states:
    "For this circuit, determine the Power Output of each Power Supply & the Power Conserved by Each Resistor. The multiple lines kind of threw me for a loop for the 10v & 20V. Thanks and any help is much appreciated.
    Jimbo Moore

    Attached Files:

  2. jcsd
  3. Mar 30, 2009 #2
    Your attachment is awaiting approval. Perhaps you can host it somewhere else (such as photobucket) and we can help you a bit quicker.
  4. Mar 30, 2009 #3
    Last edited by a moderator: May 4, 2017
  5. Mar 30, 2009 #4
  6. Mar 30, 2009 #5


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    Homework Helper

    You need to write 2 loop equations for the inner loops, remembering to take the current through the middle resistor as the sum of the 2 currents.

    Pick a direction for the current in each loop and then add voltages around the loop. They should add to 0 over any closed loop.

    You will have 2 equations. And you will have 2 unknowns I1 and I2. Just solve.
  7. Mar 31, 2009 #6
    So where does the power output of the "power supply" and the power "Conserved" come into play with the equation? Why is there 2 ends to each voltage? That's throwing me off and so is trying to understand what exactly it is asking for. What directions do these 2 voltages cause throughout the circuit? Thanks!
  8. Mar 31, 2009 #7
    Also, is there any examples on here or elsewhere that anyone knows of that have vast similarities to this equation? Or if I am to search for it, what should my keywords be? Thanks again!
  9. Mar 31, 2009 #8


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    As a first step don't you think you need to determine the current in the loops, so you can address the V*I of the voltage sources and the resistors?
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