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Help with figuring out voltage

  1. Sep 26, 2011 #1
    1. The problem statement, all variables and given/known data


    2. Relevant equations

    3. The attempt at a solution
    I got V1=18V
    Here's my work:
  2. jcsd
  3. Sep 26, 2011 #2
    Can't see the image statement. Imgur.com says image does not exist.

    Can see your work though. Is that line connecting + and - a conductor?
  4. Sep 26, 2011 #3
    Can you see that now?
  5. Sep 26, 2011 #4
  6. Sep 26, 2011 #5
    I applied Kirchhoff's Voltage law and V=IR to solve this. The final answer I got is different from yours.

    How did you get those first two lines on the left?
  7. Sep 26, 2011 #6
    I actually got a different answer just now too. I got V1 = 37.3333V
  8. Sep 26, 2011 #7
    Yeah, that's what I get.
  9. Sep 26, 2011 #8
    Would it be possible for you to check my answer to another problem as well?


    Thank you!

    I get 10.6666mA
    Last edited: Sep 26, 2011
  10. Sep 26, 2011 #9
    Need to clear one thing up before I try.

    I_s is an ammeter, right?

    Ideal ammeters have zero resistance. Since a resistance value is not given for I_s, it has to be assumed to be an ideal ammeter. Then the current is going to bypass the 8k and 4k resistors.
  11. Sep 26, 2011 #10
    Is is a current source.
  12. Sep 26, 2011 #11
    Oh, OK.
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