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Homework Help: Finding the equivalent resistance PLEASE HELP

  1. Jan 31, 2008 #1
    Finding the equivalent resistance...PLEASE HELP!!!!

    1. The problem statement, all variables and given/known data
    So I have a cube and it has resistance on every edge and I need to find what is the equivalent resistance? No numbers are given just the cube itself.

    2. Relevant equations

    3. The attempt at a solution
    How in the world do I go about solving this?!?!
  2. jcsd
  3. Jan 31, 2008 #2
    First of all, why would you make a three dimensional circuit diagram? That makes absolutely no sense. Second, I'm fairly certain this cannot be given an equivalent resistance. A square of resistors doesn't have an equivalent resistance, nor should its three dimensional equivalent. You could find a thevenin resistance, but since it is three dimensional then I don't know what you would consider what.

    Since when do people think circuits should be vectors?
  4. Jan 31, 2008 #3
    I suppose all the resistances along the edges are equal and the resistance between 2
    opposite points on the cube is needed.

    Using symmetry you can see that some of the corners have the same potential. You can connect these and it becomes an easy problem with parallel and series resistances
  5. Feb 1, 2008 #4
    Thank you for your help! Well my teacher decided to give us this problem as extra credit worth 20 points which is huge!!! So I am determined to figure out! Thanks again!
  6. Feb 1, 2008 #5
    I'm curious to see what your teacher says the answer is. Would you mind posting it when you know it?
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