ENGR 205, Spring 2012 [Homework 5 (Chapter 6)]

Dr. Fahad Alajmi page 1

*P6.1

For the circuit shown in figure 1, find the equivalent inductance between terminals a and b?

*P6.2

In the circuit shown in figure 2, find the equivalent capacitance between terminals A and B if

=2uF?

Figure 2

*P6.3

For each of the circuits shown in figures 3, find the equivalent capacitance between terminals X and Y?

Figure 3

Figure 1

Nonstar problems are bounces

For Section Dr.Ali

30 F

20 F

C

C

8

2 uF

ENGR 205, Spring 2012 [Homework 5 (Chapter 6)]

Dr. Fahad Alajmi page 2

P6.4

The current through a 2 F as a function of time is as shown in Figure 4. At time t=0, the voltage across the capacitor terminals is V. Calculate the voltage, power and energy for the capacitor?

Figure 4

*P6.5

For the circuit shown in figure 5, find the equivalent inductance between terminals a and b?

Figure 5

*P6.6

For each of the circuits shown in figures 6 , find the equvalent inductance between terminals X and Y .

Figure 6

50

-50

-- 30

20 H

12 H

5H

9H

ENGR 205, Spring 2012 [Homework 5 (Chapter 6)]

Dr. Fahad Alajmi page 3

P6.7

The current through a 2H as a function of time is as shown in figure 7. Calculate voltage, power and energy?

Figure 7

*P6.8

For the circuit shown in figure 8, if and (0) = 10A, find (t), and ?

Figure 8

P6.9

The two series – connected capacitors in figure are connected to the terminals of a black box at t=0. The resulting current i(t) for t 0 is known to be .

a) Replace the original capacitors with an equivalent capacitor and find V0(t)≥0. b) Find for t ≥0. c) Find for t ≥0. d) How much energy is delivered to the black box in the time interval 0 ≤ t ≤ ∞? e) How much energy was initially stored in the series capacitors? f) How much energy is trapped in the ideal capacitors? g) Show that the solutions for and agree with the answer obtained in (f)?

20

4 8 A

2 H

400

ENGR 205, Spring 2012 [Homework 5 (Chapter 6)]

Dr. Fahad Alajmi page 4

Figure 9

P6.10

The two parallel inductors in figure are connected across the terminals of a black box at t =0. The resulting voltage for t>0 is known to be . It is also known that and

a) Replace the original inductors with an equivalent inductor and find i(t) for t ≥ 0. b) Find for t ≥0 c) Find for ≥ 0 d) How many energy is delivered to the black box in the time interval 0≤ t ≤ ∞ ? e) How much energy was initially stored in the parallel inductors ? f) How much energy is trapped in the ideal inductors ? g) Show that your solution for and agree with the answer obtained in (f) ?

Figure 10

10

6 A

40 H