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ViolentCorpse
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Homework Statement
For the circuit shown (in the attachment), find iL(0+) and Vc(0+).
Homework Equations
V=IR
The Attempt at a Solution
At t=0-; the inductor can be replaced by a short-circuit and the capacitor by an open circuit. This shorts out the resistor so by Ohm's law, the voltage drop across it is 0V. Since all the elements are in a parallel combination, that means the voltage across each element is 0V. And we know that Vc(0-)=Vc(0+); therefore Vc(0+)=0V.
For iL, since the inductor acts like a short circuit and at t=0-, all the current passes through this short alone. So iL(0-)=iL(0+)= 4A.
Right?
Now here's my question: An open-circuit equivalent of capacitor means that the capacitor is charged and thus has a voltage across it. Yet in this problem, my analysis yields Vc(0)=0V. I find this result contradictory to my solution approach because I started by open-circuiting the capacitor only to later arrive at the result that it has developed no voltage at all across it; for how can a charged capacitor not have any voltage across its plates?
This is my conceptual confusion. I'd really appreciate your help guys! :)
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