r1=5*10^(-2);
r2=7*10^(-2);
n=400;
i=2;
f=1.5*10^(-4);
disp("Part a");
d=r2-r1;
a=%pi*d^2/4;
b=f/a;
disp("the flux density (in T) is"); disp(b);
disp("Part b");
mmf=n*i;
disp("the magnetomotive force (in At) is"); disp(mmf);
disp("Part c");
r=(r1+r2)/2;
l=2*%pi*r;
h=mmf/l;
disp("the manetizing intensity (in At/m) is"); disp(h);