Question

In the circuit of Figure 2, assuming that the switch has been closed for a long time. Find iL and i(t) for t>0. Plot the graph using i(t) vs t. Find the time constant

w U HS O=16

Answer 1

for 22 - finding 5H I 24H AH {2H time-constant We are not considering 82 for time-constant because when switch is Open, the current decay will not depend on source 6 w (Rez) as : 65231 side 6x2 6+2 R. (Lell as = 5+ 3112114 1.5 : 5 +1+1) 3' 3'), 18+12+6 t24 TAB = 5.92 st = 0.667 st = 25 C[t) - 5+ 24 = 5.92 H 26

fom Simplifying the calculation, current sowice is converted to voltage 3.432 Source SA 17.143 V Before Switch is opened 3.438 SH RR mm I 17.143V 343 243 344 Short-ckt all inductor 3.432 22 17.143 I = 17.143 2+3.43 = 3.157 A = 3.157 A After switch is open All corrents are zero (" No source) (t)= iloo) + (160)-11 0) 8 % = 3.157 e the į (60) = 0 ů (0) = 3.157A = 3.157 - 31/2 -34/2 A. After switch is open | i(t) = - ų (t) = -3.157 e Series

20 25

20

Continuous powergui о+100 -о -о- о +, от ООО по- V=17.1439 + ООО го