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UNIVERSITI TEKNIKAL MALAYSIA MELAKAFACULTY OF ELECTRONIC ENGINEERING AND COMPUTER ENGINEERING

BENT 1123 ELECTRICAL CIRCUIT ANALYSISTUTORIAL 3 (First-Order Circuits)

Source-Free RC Circuit.

1. Determine the time constant for the circuit in Fig. 1

10 k 20 k

100 pF

40 k 30 k

Figure 1

2. The switch in Fig. 2 opens at t=0. Find vo for t > 0.

2 k t=0

+

6 V vo 4 k 50 F

Figure 2

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Source-Free RL Circuit.

3. For the circuit in Fig. 3, find io for t >0.

3 t=0 4H

io

4 24 V 8

Figure 3

4. Calculate the time constant of the circuit in Fig. 4.

20 k 10 k

5 mH40 k 30 k

Figure 4

+_

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Step Response of an RC Circuit.

5. Consider the circuit in Fig. 5. Find i(t) for t < 0 and t > 0.

Figure 5

6. Find v(t) and i(t) in the circuit of Fig. 6.

Figure 6

Step Response of an RL Circuit.

7. Find v(t) for t > 0 in the circuit of Fig. 7 if the initial current in the inductor is zero.

Figure 7

6[1u(t)] A

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8. Obtain v(t) and i(t) in the circuit of Fig. 8.

Figure 8

20u(t) V