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diff --git a/3760/CH4/EX4.59/Ex4_59.sce b/3760/CH4/EX4.59/Ex4_59.sce
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+clc;
+v=220; // rated voltage of motor
+i=15; // rated current of motor
+ra=0.4; // net armature resistance
+n=1500; // speed for which magnetization curve is given
+IF=[ 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 1.2 1.45];
+EA=[120 160 197 210 220 228 232 236 243 248];
+plot(IF,EA);
+xlabel('field current');
+ylabel('voltage');
+title('magnetising curve');
+disp('case a');
+ifg1=0.15; // initial generator field current
+ifg2=1.4; //  final generator field current
+ifm=0.6; // motor field current
+// corresponding ifg1 counter EMF of generator from magnetization curve is 
+Ea1=60;
+vd=i*(ra+ra); // voltage drop in two armature resistance
+Ea2=Ea1-vd; // counter EMF of motor
+// but motor counter EMF for 0.6 A field current at 1500 rpm is
+Ea3=210; 
+nmin1=(Ea2/Ea3)*n; // minimum motor speed
+// corresponding ifg2 counter EMF of generator from magnetization curve is 
+Ea4=247;
+Ea5=Ea4-vd; // counter EMF of motor
+nmax1=(Ea5/Ea3)*n; // maximum motor speed
+sr=nmax1/nmin1; // speed range
+printf('Speed range for full load armature current is %f:1\n',sr);
+// for no load generator counter EMF= motor counter EMf
+nmin2=(Ea1/Ea3)*n; // minimum motor speed
+pr=((nmin2-nmin1)/nmin2)*100;
+printf('Percent speed drop from no load to full load for condition of minimum speed is %f percent\n',pr);
+// for maximum generator field current generator counter EMF= motor counter EMf at no load
+nmax2=(Ea4/Ea3)*n; // maximum motor speed
+sr=nmax2/nmin2; // speed range
+printf('Speed range for full load armature current is %f:1\n',sr);
+pr=((nmax2-nmax1)/nmax2)*100;
+printf('Percent speed drop from no load to full load for condition of maximum speed is %f percent\n',pr);
+disp('case b')
+// for generator field current=1 A counter EMF from magnetization curve is 
+Ea6=236;
+Ea7=Ea6-vd; // motor counter EMF at full load
+Ea8=(Ea7/(2*nmax1))*n; 
+printf('Motor counter EMF for %f rpm is %f V\n',n,Ea8);
+// Corresponding to Ea8, field current is 
+ifmi=0.25;
+printf('Minimum motor field current is %f A\n',ifmi);