My question applies to the case when the switch opens. By applying KCL in order to get a first order diff equation, the following problem arises when I choose different current directions (which shouldn't happen because KCL says the current direction doesn't matter because it will be fixed after all is said and done.(adsbygoogle = window.adsbygoogle || []).push({});

So the first one (NODE A) has

v/(RC)+dv/dt = 0 whose solution is $$Ke^{^{\frac{-t}{RC}}}$$

while the next case (NODE B) has

v/(RC)-dv/dt = 0 whose solution is $$Ke^{^{\frac{t}{RC}}}$$

I know the correct form is the first one, with a -t for the argument but doesn't a KCL "ignore" current direction and should then produce the solution, irregardless of direction?

Am I missing something?

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# KCL and First order circuit theory

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