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diff --git a/3760/CH4/EX4.69/Ex4_69.sce b/3760/CH4/EX4.69/Ex4_69.sce
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+clc;
+p=10000; // rated power of transformer
+n=900; // speed of motor
+v=400; // rated voltage of motor
+ra=1; // armatyre resistance
+rf=400; // field resistance
+ne=0.85; // efficiency at rated load 
+l=((1/ne)-1)*p; // total losses
+disp('case a');
+pi=p+l; // power input 
+il=pi/v; // line current
+ia=il-(v/rf); // armature current
+la=ia^2*ra; // armature circuit losses
+lf=v*(v/rf); // shunt field losses
+wo=l-la-lf; // no load losses
+iao=wo/v; // no load current neglecting armature losses at no load
+printf('No load armature current is %f A\n',iao);
+disp('case b');
+Ea1=v-ia*ra; // counter EMF at rated load
+il=20; // current drawn by motor
+ia=il-(v/rf); // armature current
+Ea2=v-ia*ra; // counter EMF at line current of 20 A
+n2=(Ea2/Ea1)*n; 
+printf('Speed of motor while drawing current of %d A from mains is %f rpm\n',il,ceil(n2));
+disp('case c');
+k=(Ea1*60)/(2*%pi*n); // constant term in counter EMF formula
+T=98.5; // electromagnetic torque
+ia=T/k; 
+printf('Armature current at given torque is %f A',ceil(ia));