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Homework Help: Quick current question

  1. Nov 2, 2005 #1
    a very simple question that i have no idea about:
    can you say that a current of 1A to the right is also a current of -1A to the left?
     
  2. jcsd
  3. Nov 2, 2005 #2
    Well, I don't really know, but that's what happen when you invert the inputs of an amperemeter.

    So, it's either a device convention to tell you the current go the other way or intensity is really counted negatively.

    In fact, I don't really know neither, but I'm sure a guru is gonna answer us :p

    Kyon
     
  4. Nov 2, 2005 #3
    After a quick google search, I think I've found the answer: using + and - for current intensity is just a convention to indicate the direction of the current.

    Positive intensity if the current go in the same direction as you decided on your drawing, negative otherwise. Just a convention.

    When you calculate intensity, I guess you should get positive results only.

    Kyon.
     
  5. Nov 2, 2005 #4
    well, i was wondering about it in the context of working out current into/out of junctions, and it seemed important

    cheers!
     
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