(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

So I need to find the total voltage across the current source.

Looking at the attachment, I took

front square: B_______C

...................|..............|

...................|..............|

...................A_______D

back square: E_______H

...................|..............|

...................|..............|

...................F_______G

2. Relevant equations

node analysis

3. The attempt at a solution

So I used node analysis at each corner to get a set of equations:

-g6Vc-g1Ve-g3Vg+(g3+g1+g6)Vh=0.001

-g5Vd-g4Vf+(g5+g4+g3)Vg-g3Vh=0

-g8Va-g2Ve+(g8+g4+g2)Vf-g4Vg=0

-g7Vb+(g1+g7+g2)Ve-g2Vf-g1Vh=0

-g12Va+(g12+g9+g7Vb)-g9Vc-g7Ve=0

-g9Vb+(g9+g10+g6)Vc-g10Ve-g6Vh=0

-g11Va-g10Vc+(g5+g10+g11)Vd-g5Vg=0

(-g12-g11-g8)Va+g12Vb+g11Vd+g8Vf=0.001

where g(x) is the conductance=1/R(x)

So I notice this as 8 equations with 8 unknowns. However, when I plug this into matlab,

I get (Warning: Matrix is close to singular or badly scaled.)

Is there a problem with my equations?

Any help would be appreciated.

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# Homework Help: Resistor Cube Problem

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