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Homework Help: Calculating potential difference

  1. May 3, 2010 #1
    1. The problem statement, all variables and given/known data

    In a 50 V circuit with a 400 Ohm resistance and a 600 Ohm resistance in series; Point A is between the two resistors and point B is to the right of the 600 Ohm resistor. Charge is moving from right to left.

    2. Relevant equations

    V=IR

    3. The attempt at a solution
    The answer is supposed to be 30 V, but why isn't it 50 V?
     
    Last edited: May 3, 2010
  2. jcsd
  3. May 3, 2010 #2

    ideasrule

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    In parallel? It seems, from the rest of the question and the answer, like they're in series.
     
  4. May 3, 2010 #3

    tiny-tim

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    Hi tmusgrove! :smile:
    How can it be 50 V ?

    That's the potential difference across both resistors. :wink:
     
  5. May 4, 2010 #4
    With TinyTim's reminder that the whole potential difference was 50, I could solve the problem. 600 Ohms and 400 Ohms = 1000 Ohms. 600 is 3/5 of 1000. 3/5 of 50 = 30. So, the answer is 30 V.
     
  6. May 4, 2010 #5

    tiny-tim

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    Yup! :biggrin:
     
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