Page 64 - Schaum's Outline of Theory and Problems of Electric Circuits

CHAP. 4]
Then, I ¼ V 1 =10 ¼ 0:118 A. ANALYSIS METHODS 53

4.11 Find the voltage V ab in the network shown in Fig. 4-25.

Fig. 4-25

The two closed loops are independent, and no current can pass through the connecting branch.
30
I 1 ¼ 2A I 2 ¼ ¼ 3A
10
V ab ¼ V ax þ V xy þ V yb ¼ I 1 ð5Þ 5 þ I 2 ð4Þ¼ 3V

4.12 For the ladder network of Fig. 4-26, obtain the transfer resistance as expressed by the ratio of V in
to I 4 .

Fig. 4-26

By inspection, the network equation is
2 32 3 2 3
15 5 0 0 I 1 V in
6 5 20 5 6 7 6 0 7
6 0 7 I 2 7 ¼ 6 7
76
4 0 5 20 5 54 I 3 5 4 0 5
0 0 55 þ R L I 4 0
R ¼ 5125R L þ 18 750 N 4 ¼ 125V in
N 4 V in
I 4 ¼ ¼ ðAÞ
R 41R L þ 150
V in
and R transfer;14 ¼ ¼ 41R L þ 150 ð
Þ
I 4

4.13 Obtain a The ´ venin equivalent for the circuit of Fig. 4-26 to the left of terminals ab.
The short-circuit current I s:c: is obtained from the three-mesh circuit shown in Fig. 4-27.