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Homework Help: Superposition question

  1. Apr 30, 2012 #1
    1. The problem statement, all variables and given/known data
    the question is find the current through R1

    R1= 10 Ohms R2=8 ohms
    current source=9A

    2. Relevant equations

    3. The attempt at a solution
    I have tried removing the current source and i get a short circuit on R1 and hence i obtain a current of 2.25A

    Attached Files:

  2. jcsd
  3. Apr 30, 2012 #2
    What you are looking for are kirschoff's laws:
    The current entering any junction is equal to the current leaving. So at the top I1 enters and use that together with the "voltage law" then you get the answer
  4. Apr 30, 2012 #3
    When using superposition on current sources, you should open, instead of shorting, circuit that branch.

    That may be where your problem lies.
  5. Apr 30, 2012 #4
    Yes didn't realize that i needed to make the current source open circuit. thanks!
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