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Homework Help: Figuring this circuit out. HELP!

  1. Feb 10, 2008 #1
    Okay I have to show that between points a and b the resistance (ab) is equal to 27/17 ohms.

    Here's the diagram:

    http://img231.imageshack.us/img231/4614/testln9.jpg [Broken]

    The hint was given to determine the emf/I where I is the current through the battery.
    I've found different ways of getting 27/17 out of it but I need to be able to explain why.
    Last edited by a moderator: May 3, 2017
  2. jcsd
  3. Feb 10, 2008 #2
    It's not obvious to me on how to combine the resistances so I'd use loop or nodal analysis.
  4. Feb 10, 2008 #3
  5. Feb 10, 2008 #4
    I forgot to mention that the EMF is connected accross points a and b
  6. Feb 11, 2008 #5
    I'm sure this is all in your text but:

    Loop Analysis

    Nodal Analysis

    Y Delta Transformation

    If you use the Y Delta method remember how resisters add based if they are in series or parallel. If you use either loop or nodal analysis then add up the current going out of node a or into node b. You'll do the same thing if you use loop analysis but you'll have to convert from current to voltage via ohms law.
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