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MOST difficult circuit ever made

  1. May 13, 2008 #1
    How to find different resistance out of 5 same and one different resistance in circuit.?
    image of resistances are shown here
    http://www.pictures.pk/viewer.php?id=rgh1210158811g.JPG

    in which 5 are same and one is different. how to recognize the different resistance in the circuit through ohm meter
    1. The problem statement, all variables and given/known data



    2. Relevant equations



    3. The attempt at a solution
    1. The problem statement, all variables and given/known data



    2. Relevant equations



    3. The attempt at a solution
     
    Last edited by a moderator: May 14, 2008
  2. jcsd
  3. May 14, 2008 #2

    Defennder

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    Er, what are the resistances? And you want to find the equivalent resistance between which two points?
     
  4. May 14, 2008 #3
    we just have to find the different reistance in the circuit....
     
  5. May 14, 2008 #4

    Hootenanny

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    I'm sorry, but I really don't understand the question. Could you please post the question verbatim?
     
  6. May 14, 2008 #5
    just paste the link starting with pictures.pk and see the figure:yuck:
     
  7. May 14, 2008 #6

    Hootenanny

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    I have done, but that only shows the diagram. I have no idea what the question is?!
     
  8. May 14, 2008 #7

    Borek

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    I think you are given circuit and the ohmeter and you are told that 5 resistances are identical, while 6th is different - and you have to find this 6th just by measuring resistance between any points in the circuit.

    I also suppose you are not allowed to cut wires :wink:

    impaxion: is there a preset limit to number of measurements you can make, or not?
     
  9. May 14, 2008 #8

    CEL

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    The circuit is symmetric. If all resistances were equal, the measurement across any of them would show the same result (the resistance in parallel with the rest of the circuit).
    Since there is a different resistance, the measurement across it will be different from the other measurements
     
  10. May 14, 2008 #9

    Redbelly98

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    It might not be in English.

    At any rate, I think Borek has provided an accurate phrasing of what is being asked.
     
  11. May 15, 2008 #10

    Dick

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    Possibly true. It may be too hard for english speakers. I can't figure the problem out and I speak english. But I do agree the problem is pretty clear.
     
  12. May 15, 2008 #11

    Dick

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    As drawn the circuit is symmetric along an axis through the center of the drawing. If you make two resistance measurements from a point on the axis to two symmetrical points off of the axis and get the same value, then the 'different resistance' must be one of the resistors that is rotated into itself by the symmetry, otherwise it's one of the others. That narrows the search down. Now find more symmetry axes. This isn't hard. You can really picture the circuit as lying on the edges of a tetrahedron. That's a good question!
     
    Last edited: May 15, 2008
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