(Solved): In the circuit of Figure 3R1=3,R2=3,R3=6,R4=4,R5=4,R ...

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In the circuit of Figure $$3R_1=3?,R_2=3?,R_3=6?,R_4=4?,R_5=4?,R_6=8?$$, $$L=20\mathrm{mH}$$, and $$V_s=12\mathrm{V}$$. The switch $$\mathrm{S}$$ is closed for a long time. At $$t=0\mathrm{s}$$, the switch $$\mathrm{S}$$ opens. a) Calculate the voltage across the resistor $$R_4$$ and the inductor current in steady-state while the switch $$S$$ is closed. b) What is the energy stored in the inductor before the switch is opened. c) Calculate the time constant of the circuit when the switch is open; d) Plot the current $$I_L(t)$$ from $$t=?5\mathrm{ms}$$ to $$t=25\mathrm{ms}$$; Figure 3: Circuit diagram for Question 3