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CIRCUIT LAWS

[CHAP. 3

Fig. 3-8

Fig. 3-9 The branch currents within the enclosed area cannot be calculated since no values of the resistors are given. However, KCL applies to the network taken as a single node. Thus, 2:0  3:0  4:0  I ¼ 0

3.4

or

I ¼ 5:0 A

Find the equivalent resistance for the circuit shown in Fig. 3-10.

Fig. 3-10 The two 20- resistors in parallel have an equivalent resistance Req ¼ ½ð20Þð20Þ=ð20 þ 20Þ ¼ 10 . This is in series with the 10- resistor so that their sum is 20 . This in turn is in parallel with the other 20-

resistor so that the overall equivalent resistance is 10 .

3.5

Determine the equivalent inductance of the three parallel inductances shown in Fig. 3-11.

Mahmood_Nahvi_eBook_Schaum_s_Outlines_Theory_An  
Mahmood_Nahvi_eBook_Schaum_s_Outlines_Theory_An  
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