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Homework Help: Total resistance through cubic circuit

  1. Oct 7, 2008 #1
    1. The problem statement, all variables and given/known data

    Suppose a resistor R lies along each edge of a cube (12 resistors in all) with connections at the corners. Find the equivalent resistance between two diagonally opposite corners of the cube


    2. Relevant equations

    [tex]\Sigma[/tex]I = 0 at a node (a junction)

    [tex]\Sigma[/tex]V = 0 through a loop

    V=IR

    3. The attempt at a solution


    Not quite sure how to do this one algebraically. Would I just add up all the V/Is? how?
     
  2. jcsd
  3. Oct 7, 2008 #2
    Not quite sure where to start...can anyone help me?
     
  4. Oct 7, 2008 #3
    How about opening the cube out so it's flat and looking at it that way.
     
  5. Oct 7, 2008 #4
    Interesting...is that necessary though, or could I just apply kirchoff's laws to it as it is?
     
  6. Oct 7, 2008 #5
    I count from any one node:
    3 paths to 3 nodes which then connect by:
    6 paths to 3 nodes which then connect by:
    3 paths to 1 node.

    connecting the 3 nodes together with wires should change nothing.
     
  7. May 25, 2009 #6
    are you saying just ignore those 6 connections?
     
  8. May 25, 2009 #7
    I think the post I was responding to was deleted.
     
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