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Homework Help: Find the potential Difference

  1. May 9, 2008 #1
    1. The problem statement, all variables and given/known data
    http://img241.imageshack.us/img241/1087/09052008hf9.png [Broken]
    What is the potential difference across (i) AB (ii) BC.
    2. Relevant equations
    ??
    3. The attempt at a solution
    (i) [tex]\frac{200}{400} \times 6 = 3V[/tex]

    Is this right? :confused:
     
    Last edited by a moderator: May 3, 2017
  2. jcsd
  3. May 9, 2008 #2
    I think the easiest way to do this would be to use equivalent resistances to find the current. After that it is very easy
     
  4. May 9, 2008 #3
    I didn't understand...
     
  5. May 10, 2008 #4

    alphysicist

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    Homework Helper

    Hi looi76,

    We know the total resistance between A and B is 200 ohms. What is the total resistance between B and C?
     
  6. May 10, 2008 #5
    The total resistance between B and C is 100 because they are connected in parallel. So, [tex]\frac{200}{(100 + 200)} \times 3 = 2V[/tex]

    Is this correct?
     
  7. May 10, 2008 #6

    Defennder

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    Homework Helper

    No, that is not the total resistance between B and C. They are both in parallel. What is the formula for resistance connected in parallel?
     
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