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Homework Help: Current, voltage, power

  1. Feb 9, 2010 #1
    1. The problem statement, all variables and given/known data

    http://img69.imageshack.us/img69/3523/42317761.jpg [Broken]
    http://img194.imageshack.us/img194/7240/82479056.jpg [Broken]

    2. Relevant equations

    3. The attempt at a solution

    The answer is 400w and 1ma respectively, but how do I get to it?
    Last edited by a moderator: May 4, 2017
  2. jcsd
  3. Feb 9, 2010 #2
    How much power does a current source deliver to a circuit? On what depends it?
    Can you figure out what the potential of the various parts of the circuit is?

    For part b:

    1. introduce two unknown potentials for the two points where 3 resistances meet. The
    potentials at the top and bottom of the circuit are +40 mv and 0.

    2. compute the currents in all five resistors as a function of the 2 unknown potentials

    3. use Kirchhofs current rule in the points with unknown potential from step 1 to set up 2 equations for the unknown potentials

    4. solve the equations

    5. compute any current needed for the answer
  4. Feb 9, 2010 #3
    for part a should I simplify the circuit? otherwise I am still lost on how to do it

    and I am even more confused by your explanation in part b, which one are you referring when you say potential at top and bottom?
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