Numerical # 1
For an R-L circuit, the voltage v(t ) and current i(t ) are given as
V(t) = 10cos(377t); i(t) = 5 cos(377t+60˚)
Sketch v(t ) and i(t ) for t = 0 to 20 milliseconds.
Solution
MATLAB Script
% RL circuit
% current i(t) and voltage v(t) are generated; t is time
t = 0:1e-3:20e-3;
v = 10*cos(377*t);
a_rad = (60*pi/180); % angle in radians
i = 5*cos(377*t + a_rad);
plot(t,v,'r*',t,i,'go')
title('Voltage and Current of an RL circuit')
xlabel('Sec')
ylabel('Voltage(V) and Current(mA)')
text(0.003, 1.5, 'v(t)');
text(0.009,2, 'i(t)')
The output of program can be seen in figure below
