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How to draw a circuit from a word problem.

  1. Jul 25, 2011 #1
    Homework Question:

    Four identical 4Ω resistors have been connected in such a way that their total resistance is 4Ω. Draw a diagram to show how they are connected.

    My Question:

    How do you solve a question like this? How do you classify it as a parallel or series circuit or does it even matter?
  2. jcsd
  3. Jul 25, 2011 #2


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    Homework Helper

    For resistors in series you add and in parallel you add the reciprocals right?

    So automatically you can see that the four resistors are not all in series and not all in parallel right?

    So what happens if you have three in parallel and one in series, what will happen? (greater, less or equal 4)

    If it is equal to four then you stop, if not you continue to just create possible combinations in your mind. You will easily see that you can't just place a 4Ω resistor in series to get total resistance of 4Ω.
  4. Jul 26, 2011 #3


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    Staff: Mentor

    NOT the answer they were looking for :biggrin:


    Attached Files:

  5. Jul 26, 2011 #4
    try adding 2 resistors in parellel. what result you get? ... Now look what else you need to reach 4Ω ...
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