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Fizzicist
Oct7-08, 12:30 AM
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

\SigmaI = 0 at a node (a junction)

\SigmaV = 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?

Fizzicist
Oct7-08, 01:02 AM
Not quite sure where to start...can anyone help me?

Rake-MC
Oct7-08, 01:12 AM
How about opening the cube out so it's flat and looking at it that way.

Fizzicist
Oct7-08, 01:28 AM
Interesting...is that necessary though, or could I just apply kirchoff's laws to it as it is?

granpa
Oct7-08, 04:38 AM
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.

AROD
May25-09, 07:24 AM
are you saying just ignore those 6 connections?

granpa
May25-09, 07:35 AM
I think the post I was responding to was deleted.