Page 171 - Schaum's Outline of Theory and Problems of Electric Circuits
P. 171
FIRST-ORDER CIRCUITS
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7.48 In the circuit of Fig. 7-49, let k ¼ 0. Find v and i after the switch is closed at t ¼ 0. [CHAP. 7
t
Ans: v ¼ e ; i ¼ 1 0:5e t
7.49 Show that the segment of the circuit enclosed by the dashed box in the circuit of Fig. 7-49 is equivalent to an
inductor with value L ¼ 1=ð1 kÞ H. Hint: Write KVL between terminals AB of the dashed box.
7.50 The switch in the circuit of Fig. 7-49 is closed at t ¼ 0. Find v at t > 0 for the following values of k:
(a) 0.5, (b)1, (c)2. Ans: ðaÞ v ¼ e t=2 ; ðbÞ v ¼ 1; ðcÞ v ¼ e t
7.51 Find i, the current drawn from the battery, in Problem 7.50.
Ans: ðaÞ i ¼ 1 0:5e t=2 ; ðbÞ i ¼ 0:5; ðcÞ i ¼ 1 0:5e t
