clc;
//page no 763
//prob no. 20.2.3
d=5*10^-6;wave=1.3*10^-6;NA=0.35;
//Determination of V no.
V=(%pi)*d*NA/wave;
disp(V,'the v no. is' );
disp('from the table it is seen that 6 modes have cut off v less than 4.23 ');