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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.
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?
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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