I'm having trouble finding out which sign to use when analysing circuits. I try to be very methodical, but if I analyse the exact same circuits that were analysed in class, but in another direction (for instance, analysing clockwise what was analysed counterclockwise in class) I arrive to different results. I'm uploading an example: Here, I tried to analyse the righthand mesh clockwise, and arrived to two different equations than my teacher, who analysed it counterclockwise.
The information given in the exercise was this:
R1 = 4 Ohm
R2 = 5 Ohm
R3 = 16 Ohm
E1 = 6 V
E2 = 2 V
The upper diagram and equations are mine; the lower are my teacher's. All signs and loops (mine in red, those of my teacher in blue) weren't given in the letter of the exercise.
It obviously has something to do with the resistance in the middle. I don't see how it's possible, as they say, to analyse a circuit in different directions and arrive at the same results. This example I'm showing isn't even the only one where I had the exact same problem.
The information given in the exercise was this:
R1 = 4 Ohm
R2 = 5 Ohm
R3 = 16 Ohm
E1 = 6 V
E2 = 2 V
The upper diagram and equations are mine; the lower are my teacher's. All signs and loops (mine in red, those of my teacher in blue) weren't given in the letter of the exercise.
It obviously has something to do with the resistance in the middle. I don't see how it's possible, as they say, to analyse a circuit in different directions and arrive at the same results. This example I'm showing isn't even the only one where I had the exact same problem.
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