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

[PLAIN]http://img163.imageshack.us/img163/408/circuit2w.jpg [Broken]

We are asked to solve for I. I found I = -4 Amps.

I want to verify my answer using KVL in the bottom left mesh

2. Relevant equations

KVL

3. The attempt at a solution

I follow the convention: voltage drops are positive, which means that the first sign I hit is the sign of the voltage. Starting at the 8 ohm resistor:

- 8*(-4) + ( ????? ) - ( ?????) = 0

I am confused because we usually apply KVL using the voltage drops/rise between elements. For the current source and the 2 ohm resistor, I have the node voltages between these elements. Therefore, I don't know if the current source is + (v2 - v1) or - (v2 - v1). Same thing for the 2 ohm resistor, I hit the - sign first, but is it - (v2 -0) or - (0-v2) ????

I am a little bit confused.. thank you very much

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# KVL and node voltages

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