Electric Circuits 2 EE 2351 4
2 RL Circuit
The switch in the RL circuit in Figure 2 has been in position \textcircled{1} for a long time. At $t = 0$,
the switch moves to position \textcircled{2} (the switch opens) and stays there. Assuming that $I_o > 0$
for the constant current source,
(a) find $v_L(t)$ for $t > 0$ (if you want, you can write $v_L(t)$ by circuit inspection; you don't
need to show the differential equation); and
(b) sketch $v_L(t)$ for $t > 0$.
Note: the answers can only use the circuit constants $I_o$, $R_o$, $R_1$, $R_2$ and $L$, and the time
variable $t$.
t=0
R1
Io
Ro
R2
Figure 2. RL circuit.
000
+
L
vL(t)
