Not really a problem, but we're learning about source-free RL circuits and the instructor was deriving the current w.r.t time. I've actually seen this derived a few times but one thing has always bothered me.
Looking at this picture recreated from the text
The equation dervied from it says:
Ri + vL = 0
which implies vR + vL = 0
but I've always thought that with KVL you simply write down the first sign you hit when tranversing the circuit, i.e., why is the equation not
-vR + vL = 0
Surely since the two components are in parallel the voltage drop across them has to be equal??!
Thanks if anyone can clear up my confusion
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