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Homework Help: Circuits analysis with independent current source

  1. Sep 10, 2012 #1
    1. The problem statement, all variables and given/known data

    https://www.edx.org/static/content-mit-6002x/images/circuits/H1P2.79e52b492b94.png [Broken]

    2. Relevant equations

    It's been a while since I've done KCL/KVL, could be that I'm being just being stupid.

    I'm trying to find v1, i4, and the power in all the circuit elements.

    3. The attempt at a solution

    I just used KCL at the top node and got 5 as the voltage. I called the top node "A". A + (A-4)/3 = 8.

    From there, I got that v1 equals 5 V because there is no resistor there(which is wrong), and the values of i1-3(16/3, 5, 1/3). i4 I GUESS is 1/3, but I don't think that is right. Power of the 1 ohm resistor is 25, and 1/3 for the 3 ohm resistor.

    So apparently, I've screwed up. Help?
    Last edited by a moderator: May 6, 2017
  2. jcsd
  3. Sep 10, 2012 #2


    User Avatar

    Staff: Mentor

    Check your work on the KCL: A + (A-4)/3 = 8. A=5 doesn't satisfy the equation.
  4. Sep 10, 2012 #3
    Ah, I see. God, that was stupid. If I have more problems(probable), I'll post them on this thread.
  5. Sep 16, 2012 #4
    Hey man! How did you find other problems? Can you give me solutions? plz)
  6. Sep 16, 2012 #5
    PM me. What problems are you having?
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