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How do u know the direction of the current?

  1. Oct 23, 2005 #1
    Hello everyone, 'im trying to figure out the potential difference between Va-Vb but i'm confused. here is the picture:
    I figured out the current in battery 1, 2 , and 3.
    In Figure 27-40, the resistances are R1 = 1 , R2 = 2.2 , and the ideal batteries have emfs 1 = 2.0 V, and 2 = 3 = 3 V;

    Since Batter 2 and 3 have the bigger amount of engery wouldn't it overcome the direction that Battery 1 has? But then current would be going from negative to positve?
  2. jcsd
  3. Oct 23, 2005 #2

    James R

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    It is possible for current to flow "backwards" through a battery. Kirchhoff's rules will tell you the direction.
  4. Oct 23, 2005 #3
    yes, it will just cancel out the effects of that battery and current will go the opposite direction
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