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Homework Statement
I felt some more practice for this was needed and I want to make sure I really understand. The circuit is given:
I'm asked to find the current in the inductor just before the switch is closed ##( i_L(t = 0^-) )##.
Then I'm asked to find ##v_L## at the instant just after the switch is closed ##( v_L(t = 0^+) ).##
Homework Equations
The Attempt at a Solution
So for ##t = 0^-##, the switch is open, and so we have a simple series circuit. The circuit is in steady state and the inductor is behaving like a short circuit. Hence the current ##i_L(t = 0^-) = 3mA## because everything is in series. Also, ##v_L(t = 0^-) = 0V##.
That seemed simple enough.
Now I need to find ##v_L(t = 0^+)##.
So first off, for ##t = 0^+##, the inductor remembers it's current from before, so ##i_L(t = 0^-) = i_L(t = 0^+) = 3 mA##.
Now since the switch is closed does that mean the current source gets short circuited?
Would that mean ##v_R = IR = (3 mA)(2k) = 6V##?
Now KVL would give ##v_R - v_L = 0 \Rightarrow v_L(t = 0^+) = 6V##.
Is this even reasonable?