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Homework Help: Basic Circuits - Equivalent Resistance

  1. Jan 12, 2009 #1
    1. The problem statement, all variables and given/known data
    circ.jpg


    Find the Resistance between terminals B-C, B-D
    2. Relevant equations



    3. The attempt at a solution

    The book says that the 2 80-ohm resistors are in parallel for terminals A-B, and the answer for B-C=90ohms, B-D=85ohms. I don't quite understand why this is. Is it because the 2 80ohm resistors are in series between terminals B-C and B-D, and therefore it short circuits because the other path (wire only) is 0 ohms? Does this mean that whether the resistors are in series or parallel depends on the path taken?
     
  2. jcsd
  3. Jan 12, 2009 #2

    berkeman

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    Staff: Mentor

    Correct about the short circuit around the 80 Ohm resistors for the path B-C and B-D.
     
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