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Homework Help: Current, Power, and Energy problem

  1. Oct 21, 2005 #1
    Okay, here's the problem:
    http://www.ihostphotos.com/show.php?id=174911" [Broken]

    Already did it once, but then I realized my "method" :rolleyes: looked good, but wasn't correct. Is there two loops for this problem, to start, or what? I get the formulas and the laws, but something is throwing me as to starting it.
    Last edited by a moderator: May 2, 2017
  2. jcsd
  3. Oct 21, 2005 #2
    Okay, now this one is the RIGHT thread:wink:
    Last edited: Oct 21, 2005
  4. Oct 22, 2005 #3
  5. Oct 22, 2005 #4


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    Use Kirchoff Rules.
  6. Oct 22, 2005 #5
    Okay, did that. Only problem was when I got to b) and c), since the power I calculated as being deilvered by the 12-V battery seems WAY too big (132W).

    Take a look:
    Part a)
    http://www.ihostphotos.com/show.php?id=175479" [Broken]

    And then Parts b) and c) (where I may have slipped up):
    http://www.ihostphotos.com/show.php?id=175481" [Broken]
    Last edited by a moderator: May 2, 2017
  7. Oct 22, 2005 #6
    Is it right???
  8. Oct 22, 2005 #7
    ANYBODY think it looks correct? I'm confident on the first part, but just wondering about my answers to parts b) and c).
  9. Oct 22, 2005 #8


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    Yes, i see no problem with it.
  10. Oct 22, 2005 #9
    Okay, thanks!
  11. Oct 23, 2005 #10

    Andrew Mason

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    It is a little complicated to analyse this circuit but your answer cannot be right. Without R1 the current through the ammeter would be 5 amps. With R1 the current will be less.

  12. Oct 23, 2005 #11
    Hmm....then what should I do differently?
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