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Does this device follow Passive Sign Convention?

  1. Sep 2, 2007 #1
    I need help determining if I and V assignments follow the passive sign convention.

    Here is the image of the circuit:
    http://img178.imageshack.us/img178/9572/pic1xu2.gif [Broken]

    I know that in order for it to follow PSC the current I needs to flow towards +V. I'm not sure if that is happening in this picture.

    Please help!
    Last edited by a moderator: May 3, 2017
  2. jcsd
  3. Sep 2, 2007 #2


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    Staff: Mentor

    That looks like a symbol for an active power source. I'm not familiar with what you call the PSC. Can you provide a web pointer to the definition of that convention?
  4. Sep 2, 2007 #3
    PSC stands for Passive Sign Convention.

    The following link describes it in detail: http://morley.eng.ua.edu/E125-2PassiveConv.pdf [Broken]

    With the image that my teacher gave me, it's kind of hard for me to tell if it follows it or not. Maybe I'm not looking at it correctly...
    Last edited by a moderator: May 3, 2017
  5. Sep 2, 2007 #4


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    Science Advisor
    Gold Member

    I was just about to give you the link you just provided for passive sign convention. From that you can see that the current through a PASSIVE ELEMENT (like a resistor) has the convention of pointing to the + end. Your picture looks like the current is leaving a power source (like a battery).
  6. Sep 3, 2007 #5
    I think I got it figured out now. Thanks guys! :-)
  7. Sep 12, 2007 #6
    So tell us the answer is it PSC?? I'm also confused my professor gave us the same problem and it got me confused.. for me it looks like the current is leaving from the + end
  8. Sep 12, 2007 #7
    That is passive sign convention. If the current goes from + to -, that's PSC. If the current goes from - to +, that's ASC or Active Sign Convention.
  9. Sep 12, 2007 #8
    isen't it leaving from the + though??
  10. Sep 12, 2007 #9
    No, the current is entering on the + sign, leaving from the - sign
  11. Sep 12, 2007 #10
    alright how about if the arrow was going away from the + end toward the box.. would that be considered ASC?
  12. Sep 12, 2007 #11
  13. Sep 12, 2007 #12
    alright i think i got it one last question lol how about if the arrow was leaving from - end toward the box is that ASC or PSC?
  14. Sep 12, 2007 #13
  15. Sep 12, 2007 #14
    Alright thanks for your help...
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