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diff --git a/3760/CH5/EX5.27/Ex5_27.sce b/3760/CH5/EX5.27/Ex5_27.sce
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+clc;
+v=400; // rated voltage of synchronous machine
+vt=v/sqrt(3); // per phase rated voltage
+ps=9500; // shaft load
+xd=5; // per phase d-axis synchronous reactance
+xq=3.2; // per phase q-axis synchronous reactance
+l=500; // friction windage and core losses
+np=3; // number of phases 
+// at rated voltage excitation EMF
+Ef=v/sqrt(3); // excitation EMF
+disp('case a');
+pt=ps+l; // power developed
+// by using formula pd=np*(((Ef*Ef*sind(de))/xd)+((Ef^2*sind(2*de)*0.5*(xd-xq))/(xd*xq))), and hit and trial method we obtain value of load angle
+de=11.623; // load angle
+id=(Ef-Ef*cosd(de))/xd; // d-axis component of armature current
+iq=(Ef*sind(de))/xq; // q-axis component of armature current
+ia=sqrt(id^2+iq^2);
+printf('Armature current is %f A\n',ia);
+pf=cosd(acosd(iq/ia)-de);
+printf('Power factor is %f lagging\n',pf); 
+disp('case b');
+de=acosd((-Ef*xq)/(4*Ef*(xd-xq))+(sqrt(0.5+((Ef*xq)/(4*vt*(xd-xq)))^2)));
+pd=np*(((Ef*Ef*sind(de))/xd)+((Ef^2*sind(2*de)*0.5*(xd-xq))/(xd*xq))); // maximum power developed
+po=pd-l; 
+printf('Maximum power output is %f W',po);