Question

3. Determine iz(t) for p0 for the circuit shown. 20 mH L 50 ms os

Answer 1

® Given cércuit 2o mnt mm M 50ms 342 We need to consider the three time intervals tso, ostssoms and t> 50ml respectively. For to both switches are open For DC inductor acts as short circuit (0) = 2 = A 2.4A 1+ 4 since the inductor current cannot change instantly. 760) = 10) = 667)= 2.4A

For osts 5oms Switch s, is closed. - Inom - 2014 { 402 no current flows in 422 since aurent always choose loro resistance path. under steady stoute incluctor acts as short circuit. ico) = = 134 Ri=12 Tops T bo 20mgoms 16. ict )= (+[ivo-ice je u it)a 12+(2.4-12] é 4/202163 (it)=12_9.6e5ota ost: 50ms

For t>soms Switch, s, is closed m m it) This sudden change does not affect the inductor current because the current cannot change abruptly. - 50x Soxlo? isoms) = (soms ) = 19.-9.67*** ifoons) - isoms) = 11.214 under steady state inductor acts as short circuit. No current flows {(x) = 12 = 12A Ros = 1114 = = 0.8-2 r = kro = 30x3 = 0.0255

Hence (t) = 160) + [{soms)-i cey] e{t-som) Czce) = 12 + (1124-12] Ct-sex8").ous 2,67= 12 +0.798-400 , tz soms