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Homework Help: Resistance of an interesting circuit

  1. Sep 15, 2012 #1
    1. The problem statement, all variables and given/known data


    So each box in the picture has resistance R. Find the resistance between A and B.

    2. Relevant equations


    3. The attempt at a solution

    I got the answer to be 3,5R. But as Im not sure if I approached the problem correctly, I would like to hear what you guys got for the answer.

    Thanks in advance
  2. jcsd
  3. Sep 15, 2012 #2
    I don't see any picture.
  4. Sep 15, 2012 #3
    You dont? Thats weird, because I do. Anyway, here's the link:
    http://s17.postimage.org/pj88qy16l/vivalaresistance.png [Broken]
    Last edited by a moderator: May 6, 2017
  5. Sep 15, 2012 #4
    Ok, thanks for the link. But i still don't see the image in your main post.
    To find the equivalent resistance, you see that there is some kind of symmetry. You can break the circuit as shown in the attachment.

    Attached Files:

    • eq.png
      File size:
      24.8 KB
    Last edited by a moderator: May 6, 2017
  6. Sep 15, 2012 #5
    Thats what I did, and got 3,5R. Wasnt sure it was correct. Thanks =)

    Guess it would get more interesting if the resistances were different.
  7. Sep 15, 2012 #6


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    Homework Helper
    Gold Member

    I get that too, taking advantage of the symmetry of the problem.
  8. Sep 15, 2012 #7
    You are welcome! :smile:
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