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diff --git a/3760/CH8/EX8.3/ExA_3.sce b/3760/CH8/EX8.3/ExA_3.sce
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+clc;
+lc=0.5; // core length in metre
+dc=2.85*10^-2; // diameter of cross section of core
+lg=2*10^-3; // length of air gap
+N=500; // Number oof turns of coil
+f=0.8*10^-3; // air gap flux
+uo=4*%pi*10^-7; // permeability of free space
+HATM=[1500 2210 2720 3500 4100];
+BT=[0.9 1.1 1.2 1.275 1.3];
+plot(HATM,BT);
+xlabel('magnetic field intensity');
+ylabel('flux density');
+disp('case a');
+ur=500; // relative permeability
+Ac=(%pi/4)*dc^2; // Area of core
+Rlg=lg/(uo*Ac); // reluctance of air gap
+Rlc=lc/(uo*ur*Ac); // reluctance of iron core
+Rt=Rlg+Rlc; // Total reluctance
+I=(f*Rt)/N; // Exciting current
+printf('Exciting current in coil is %f A\n',I);
+disp('case b');
+Ag=(%pi/4)*(dc+2*lg)^2; // air gap area 
+Rlg=lg/(uo*Ag); // reluctance of air gap
+I=(f*(Rlc+Rlg))/N; // Exciting current
+printf('Exciting current after accounting for flux fringing is %f A\n',I);
+disp('case c');
+Bg=f/Ac; // Air gap flux density
+Atg=(Bg*lg)/uo; // air gap mmf
+// from the plot we can get the values of core flux density and magnetic field intensity
+Bc=1.245; // core flux density in Tesla
+H=3200; // magnetic field intensity in Ats/m
+Atc=H*lc; // core mmf
+mt=Atg+Atc; // total mmf
+I=mt/N; // Exciting current
+printf('Exciting current for third case is %f A',I);