Kirchhoff's Rules Homework Solution

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The discussion focuses on applying Kirchhoff's laws to a circuit problem, where the user has derived five equations based on the loop and junction rules. However, they encounter an issue when reducing the equations to row echelon form, resulting in zero currents, which is illogical. Feedback suggests that the user has too many loop equations and lacks junction-rule equations, indicating an incomplete system. The importance of labeling the circuit diagram is emphasized for clarity. The conversation highlights the need for a balanced approach to applying Kirchhoff's laws in circuit analysis.
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Homework Statement



Find Kirchoff's laws for this
http://postimg.org/image/d78dvdg5f/

(Actual problem has a bit more but I can do that part.)

Homework Equations



Loop rule
Junction rule

The Attempt at a Solution



I got the following equations

2e - 4i_4 - 2i_2 = 0
e - 3i_3 - i_1 = 0
e - 4i_4 - i_1 = 0
2e - 3i_3 - 2i_2 = 0
3e - i_1 - 2i_2 = 0

I used these in a matrix but when I reduced to rref I got zero's for the currents which doesn't make sense.

Thanks,

P.S This is from a 2nd year Uni course
 
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It helps to label your diagram.
You appear to have put ##e=\varepsilon/R##
I don't see where 3e comes from.

You have three loops - but 5 loop equations - this means that you will get zero lines in the matrix (some of rows are linear combinations of the others) and you appear to have no junction-rule equations: these will not have any e's in them. So your system of equations may be incomplete.
 
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