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Homework Help: Current electricity help please

  1. May 30, 2007 #1
    1. The problem statement, all variables and given/known data
    Code (Text):

       l                   l                          R1=5 ohms
    ----  V=120            l                          R2= 11 ohms
      -                   R2                        R3= 6 ohms
      l                     l                          R4=8 ohms
      l                     l                          R5=4 ohms
      l              ------------
      l              l            l
      l              l            l
      l              R3           R4
      l              l            l
      l              l           R5
      l              ------------
    Q: find the potential difference across the 4.0 ohm resistor

    2. Relevant equations

    3. The attempt at a solution
    V= IR
    V/ (R1+R2)

    (V/(R1+R2)) / 2

    ((V/(R1+R2))/2) x ((1/R4)+(1/R5))^-1
    Last edited: May 30, 2007
  2. jcsd
  3. May 30, 2007 #2


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    Homework Helper
    Gold Member

    I'm sorry, I'd try to help if i can, but I can't understand your diagram??
  4. May 30, 2007 #3


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    Gold Member

    Use the code tags to preserve the formatting of your characters.

    use [ CODE ] [ /CODE ]*

    *no whitespaces.
    Last edited: May 30, 2007
  5. May 31, 2007 #4


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    Gold Member

    Find the total resistance of the circuit, then the current I = V/Total R.

    The voltage across the 4 ohm resistor is then 4*I.

    R total = R1 + R2 + 1/(1/R3+1/(R4+R5))
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