//Chapter-2,Example2_2_6,pg 2-12

a=2*10^-6                                 //width of slit

n=1                                       //for first minimum

wavelength=6500*10^-10                    //wavelength of light 

angle=asind(n*wavelength/a)              //angular seperation 

printf('\nThe half angular width of a principal maximum is  angle =%.2f degrees\n',angle)