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Given this circuit enter image description here

Switch \$S\$ is closed for a long time (\$t<0\$). At \$t=0\$, switch \$S\$ is opened. Find expression for \$V_c\$.

I know if the circuit only has one source I could apply KCL right away. But in this case, the circuit has two sources.

love you
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    A little hint is to realise that when the switch has been closed for a long time the capacitor will be fully charged to a fixed voltage. Therefore there is only running a current in the left loop and no current in the right loop. And then try to think off what an inductor looks like after infinite time :) – Jakob Halskov Nov 10 '19 at 06:49
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    @JakobHalskov The inductor will act as a short circuit. Just making sure my work is on the right track, $V_C(0) = -22 V$, is it? – love you Nov 10 '19 at 10:18
  • Yes, exactly :) – Jakob Halskov Nov 10 '19 at 12:09
  • And as a follow up: the circuit will only have one source when the switch is opened at t=0 – Jakob Halskov Nov 10 '19 at 12:51
  • @JakobHalskov You are correct that the capacitor will have -22 V across it at t=0. But also, there will be 2 A through the inductor at this time. So you have two initial conditions: the current in the inductor and the voltage across the capacitor. The entire circuit is a series arrangement of an R, an L and a C between +24 V and ground, with two known initial conditions. For a slightly different analysis see here. – jonk Nov 11 '19 at 04:42
  • @jonk how about $i(0)$? is it 2A or 0A, and why? – love you Nov 11 '19 at 05:52

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