//example_2
//chapter 41
theta_1=30
n_qa=1.4702
theta2=asind(sind(theta_1)/n_qa)
disp("For 4000 A beam, theta_2 in degree=")
disp(theta2)

theta_1=30
n_qa=1.4624
theta2=asind(sind(theta_1)/n_qa)
disp("For 5000 A beam, theta_2 in degree=")
disp(theta2)