PRACTICAL MATLAB® FOR ENGINEERS PRACTICAL MATLAB

Alternating Current Analysis 275

Example 3.7

Let the current in the RC circuit shown in Figure 3.56 be i(t) = 5 sin(200t) A. Create the

script fi le curr_vol_RC that returns the plots of v(t) versus t and i(t) versus t, over the

range 0 ≤ t ≤ 0 .1 s.

MATLAB Solution

% Script file: curr _ vol _ RC

clf

W = 200;

R = 0.5e5;

C = 10e-8;

Ang = 1/(W*C*R);

t = 0:.001:.1;

V = (R^2+(1/W*C)^2)^.5*5*sin(W.*t-atan(Ang));

I =5*sin(W.*t);

subplot(2,1,1)

plot(t,V)

ylabel(‘Ampitude[v(t)]’);

xlabel(‘time in seconds’);

title(‘v(t) vs. t ’)

subplot(2,1,2)

plot(t,I)

title(‘i(t) vs. t ’)

xlabel(‘time in seconds’);

ylabel(‘Amplitude[i(t)]’)

The script fi le curr_vol_RC is executed and the returning plots are shown in Figure 3.57.

C= 10*10−^8 F

R = 0.5*10^5 Ω

i(t) = 5 sin(200 t) A

v(t)

FIGURE 3.56

Network of Example 3.7.