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Electric Circuits, 9th Edition P22. Designed for use in a one or two-semester Introductory Circuit Analysis or Circuit Theory Course taught in Electrical or Computer Engineering Departments. Electric Circuits 9/e is the most widely used introductory circuits textbook of the past 25 years. As this book has evolved over the years to meet the changing learning styles of students, importantly, the underlying teaching approaches and philosophies remain unchanged. | 186 Inductance Capacitance and Mutual Inductance Note that 5 V is the voltage on the capacitor at the end of the preceding interval. Then v 106 - 12.5 X 109 2 - 10 V P vi 62.5 X 1012 3 - 7.5 X 109 2 2.5 X 105 - 2 W 2 w -Cv 2 15.625 X 1012 4 - 2.5 X 109 3 0.125 X 106 2 - 2t 10 5 J. For 40 zs v 10 V p vi - 0 w z Cv1 10 J. -1------1 t zs 50 60 b The excitation current and the resulting voltage power and energy are plotted in Fig. 6.12. c Note that the power is always positive for the duration of the current pulse which means that energy is continuously being stored in the capacitor. When the current returns to zero the stored energy is trapped because the ideal capacitor offers no means for dissipating energy. Thus a voltage remains on the capacitor after i returns to zero. Figure 6.12 The variables z v p and w versus t for Example 6.5. assessment problems Objective 2 Know and be able to use the equations for voltage current power and energy in a capacitor 6.2 The voltage at the terminals of the 0.6 juF capacitor shown in the figure is 0 for t 0 and 40e-15 0 0i sin 30 000 V for t 0. Find a z 0 b the power delivered to the capacitor at tt 80 ms and c the energy stored in the capacitor at tt 80 ms. 0.6 zF r NOTE Also try Chapter Problems 6.16 and 6.17. Answer a 0.72 A b -649.2 mW c 126.13 xJ. 6.3 The current in the capacitor of Assessment Problem 6.2 is 0 for t 0 and 3 cos 50 000 A for 0. Find a v t b the maximum power delivered to the capacitor at any one instant of time and c the maximum energy stored in the capacitor at any one instant of time. Answer a 100 sin 50 000 V t 0 b 150W c 3mJ. 6.3 Series-Parallel Combinations of Inductance and Capacitance 187 6.3 Series-Parallel Combinations of Inductance and Capacitance Just as series-parallel combinations of resistors can be reduced to a single equivalent resistor series-parallel combinations of inductors or capacitors can be reduced to a single inductor or capacitor. Figure 6.13 shows inductors in series. Here the .