PRACTICAL MATLAB® FOR ENGINEERS PRACTICAL MATLAB

268 Practical MATLAB® Applications for Engineers

C = 1e-6;

w = [200:50:2000];

XL = w*L;

XC = 1./(w*C);

plot(w,XL,’o’,w, XC,’*’)

title(‘[XL(w) and XC(w)] vs w’)

xlabel(‘frequency in rad/sec’), ylabel(‘Magnitude in Ohms’)

legend(‘XL’,’XC’)

grid on

hold; plot(w,XL,w,XC)

The script fi le XL_XC is executed and the results are shown in Figure 3.49.

Example 3.2

Evaluate the impedance Z and admittance Y = (1/Z) for the circuit shown in Figure 3.50

fi rst by hand, and then by writing the script fi le Z_Y, for an angular frequency of w =

1 rad/s.

FIGURE 3.49
Plots of Example 3.1.

200 400 600 800 1000 1200 1400 1600 1800 2000

0

500

1000

1500

2000

2500

3000

3500

4000

4500

5000 [XL(w) and XC(w)] versus w

frequency in rad/sec

Magnitude in Ohms

XL

XC

FIGURE 3.50
Network of Example 3.2.

C = 1/5 F R = 4 Ω

Z L = 2 H

w = 1 rad/s