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Finding the current in each resistor - Kirchhoff

  1. Mar 19, 2014 #1
    1. The problem statement, all variables and given/known data

    Find the current in each resistor of this circuit.

    fIHg2be.png

    2. Relevant equations

    Kirchoff's Current Law

    3. The attempt at a solution

    I just need a nudge in the right direction. I am fairly sure Kirchoff's Current Law comes into play, and have counted 6 loops and 4 junctions. I am not sure where to proceed next; the problems we've done before with KCL usually gave us currents and their directions. Any help on getting started would be appreciated.

    Thank you.
     
  2. jcsd
  3. Mar 19, 2014 #2
    That should be the right approach -- a lot of equations, but it will all work out in the end. The strategy for the direction of the current is just to label each different current in the diagram with an arbitrary direction, as long as that direction is consistent every time you use it. So, for example, you would just say that the current across R6 points up (or down, if you want). It really doesn't matter. You'll find out in the end when you solve for the value of the current -- if the value is negative, that just means the current goes in the opposite direction of the arrow, and you happened to guess wrong, but it still conveys the same meaning.
     
  4. Mar 19, 2014 #3
    Thank you so much! That's the part I was missing: using arbitrary directions. I get it now.
     
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