Basic Circuit Theory Chpter5 Problems 1 The switch in Fig. 5-27 is opened at t=0, Find iz(0)and vL(0) IkQ 100V lkQ vE35mH Fig. 5-27 For prob. 1 2 The switch is closed at t=0 in Fig. 5-28. Find i(0*)and ic(0*) if the capacitor is initially uncharged l Oko 5g2 Fig 5-28 For prob. 2 3(a)The switch in Fig. 5-29 is closed at t=0. If the initial capacitor voltage and inductor current are both zero, find vr(o )and iR(0).(b) Suppose the switch in Fig. 5-29 has been losed for a long time when it is opened at t=0. Find V r(o )and iR(0) I kQ2 i 10uF 10mH Fig. 5-29 For prob. 3 4 For the circuit shown in Fig. 5-30, find i,(0),12(0), and v(0) 0.492 2H 24V Fig 5-30 For prob. 4 5 After being in the configuration shown for a long time, the switch in Fig.5-31 is opened at t 0. Determine values for is(0),i,(0 ),is(0), and.(0 100g 7592 0.8i D4V‖20g2 DaLian Maritime University
Basic Circuit Theory Chpter5 Problems 1 The switch in Fig.5-27 is opened at t = 0, Find i (0 ) and v (0 ) L + L + + - - t=0 + Li 100V 1kΩ 1kΩ L v 5mH Fig. 5-27 For prob.1. 2 The switch is closed at t = 0 in Fig.5-28. Find i(0 ) and i (0 ) if the capacitor is initially uncharged. + C + + - t=0 + - 5 Ω C v 10 V 2 F i ( )t 1 0 kΩ C i Fig. 5-28 For prob.2. 3 (a) The switch in Fig.5-29 is closed at t = 0. If the initial capacitor voltage and inductor current are both zero, find v (0 ) and i (0 ). (b) Suppose the switch in Fig.5-29 has been closed for a long time when it is opened at t = 0. Find v (0 ) and i (0 ). R + R + R + R + + - t=0 + - 1 kΩ 100V 10µF 10mH R v Ri Fig. 5-29 For prob.3. 4 For the circuit shown in Fig.5-30, find i 1 (0 ), i (0 ), and v(0 + ). + 2 + + t =0 - 2 Ω 8Ω 24 V v (t ) 1 H 0 .4Ω 2 H 1i 2 i Fig. 5-30 For prob.4. 5 After being in the configuration shown for a long time, the switch in Fig.5-31 is opened at t = 0. Determine values for i (0 ), i (0 ), i (0 ), and i (0 ). S − x − S + x + + - t=0 x i 34 V 20Ω 100Ω 75Ω 25Ω 10 mF s i x 0 . 8 i Fig. 5-31 For prob.5. DaLian Maritime University 1
Basic Circuit Theory Chpter5 Problems 6 The switch in the circuit of Fig 5-32 is a single-pole, double-throw switch that is drawn to indicate that it closes one circuit before opening the other. Assuming the switch has been in the position drawn in the figure for a long time, determine the value of v and il(a) the instant just prior to the switch changing; ( b)the instant just after the switch changes 5A 8921129 3H Fig. 5-32 For prob. 6 7 The switch in Fig. 5-33 opens at t=0 after having been closed for time immemorial. Find i2(0-),i2(0-),andi(0+),i2(0+) L30150230m Fig. 5-33 For prob. 7. 8 After being open for two days, the switch in Fig. 5-34 closes at t=0, sketch v(t) versus t and evaluation v at t=15s 1.2g 4.2H Fig. 5-34 For prob.8. 9 The switch in series with the battery in Fig. 5-35, having been closeed for a long time, is opened at t=0. Over what time interval is the voltage magnitude across the switch greater than lv? Ω2 Fig 5-35 For prob. 9 10 The switch in the circuit shown in Fig. 5-36 is opened at t=0 after being closed for a long time find v for t>o 3 mA 0.9V [2k2 Fig. 5-36 For prob. 10 Dalian maritime university
Basic Circuit Theory Chpter5 Problems 6 The switch in the circuit of Fig.5-32 is a single-pole, double-throw switch that is drawn to indicate that it closes one circuit before opening the other. Assuming the switch has been in the position drawn in the figure for a long time, determine the value of v and i (a) the instant just prior to the switch changing; (b) the instant just after the switch changes. L 5A 3H 2Ω 8Ω L i 12 Ω v + - t = 0 Fig. 5-32 For prob.6. 7 The switch in Fig.5-33 opens at t = 0 after having been closed for time immemorial. Find i (0 ), i (0 ), and i (0 ), i (0 ). L − x − L + x + t=0 x i 100Ω L i 300Ω 150Ω 50 mH 60 mA Fig. 5-33 For prob.7. 8 After being open for two days, the switch in Fig.5-34 closes at t = 0, sketch v(t) versus t and evaluation v at t = 15s. + t=0 - 6 V 1 .2Ω v (t ) 0 .3Ω 4.2H 0 .7 Ω Fig. 5-34 For prob.8. 9 The switch in series with the battery in Fig.5-35, having been closeed for a long time, is opened at t = 0. Over what time interval is the voltage magnitude across the switch greater than 1V? 10 The switch in the circuit shown in Fig.5-36 is opened at t = 0 after being closed for a long time, Find v for t > 0. x t=0 Fig. 5-35 For prob.9. 100 Ω 12 V 400µF 200µF 100 Ω + - t=0 + - 1 kΩ 3 mA 0 .9 V 2.5µF v x 2 kΩ DaLian Maritim Fig. 5-36 For prob.10. e University 2
Basic Circuit Theory Chpter5 Problems Reference answers to Selected Problems 1:0.1A,-200V(t=0),0A,0v(t→∞) 2:(0°)=c(0°)=0. 4:(a)9.6A;(b)24A;(c)96eA;(d)2.4e-A;,(e)192(e-e-) 5:(a)290mA;(b)200mA;(c)50mA;(d)277mA;(e)33.5mA 6:(a)i(0-)=4Av(0-)=0,(b)i2(0+)=4A,v(0)=48V 8:0.39V 9:2.35ms. 10:14e-0y(t>0 DaLian Maritime University
Basic Circuit Theory Chpter5 Problems Reference Answers to Selected Problems 1: 0.1A, -200V (t=0 ); 0A, 0V (t + → ∞ ). 2: i(0 )=i (0 )=0. + C + 4: (a) 9.6A; (b) 2.4A; (c) 9.6e A; (d) 2.4 e A; (e) 19.2(e - e )V. −2t −4t −4t −2t 5: (a) 290 mA; (b) 200 mA; (c) 50 mA; (d) 277 mA; (e) 33.5 mA. 6: (a) i (0 )=4A, v(0 )=0; (b) i (0 )=4A, v(0 )=48V. L − − L + + 8: 0.39V. 9: 2.35 ms. 10: 1.4e V ( t > 0). −200t DaLian Maritime University 3
