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Homework Help: Current addition

  1. Mar 9, 2005 #1
    What is I5 I think its I3-I4+I2+I1 but not surehow to add em up any tips?

    thanks
     

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  3. Mar 9, 2005 #2

    dextercioby

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    Yes,it is correct.Electric charge is conserved.With the regular choise of signs,the I_{5} should be -12A.

    Daniel.
     
  4. Mar 9, 2005 #3

    Andrew Mason

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    Think of current as water flow. The current at a point is the sum of all currents entering at that point minus all currents leaving that point. Your answer is correct.

    AM
     
  5. Mar 9, 2005 #4

    dextercioby

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    Up to the minus.

    Daniel.
     
  6. Mar 10, 2005 #5
    Thanks for the reassurance but by the way it wasnt neative
     
  7. Mar 10, 2005 #6

    dextercioby

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    It had to be.That's the rule.All currents entering a vertex are positive,while all which are leaving are negative.

    Daniel.
     
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