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+//Chapter 5:DC Motor Drives
+//Example 4
+clc;
+
+//Variable Initialization
+
+//The ratings of the motor are same as that of Ex-5.2
+V1=220 //rated voltage in V
+Ia1=100 //rated current in A
+N1=1000 //speed in rpm clockwise
+N2=800 //given speed during the dynamic braking in rpm
+Ra=0.05 //armature resistance in ohms
+Rs=0.05 //field resistance in ohms
+
+//Solution
+
+T2 = 2 //dynamic torque is twice the rated torque
+Ia2=Ia1*sqrt(T2) //since T=Kf*Ia**2
+E1=V1-Ia1*(Ra+Rs)
+E2=(Ia2/Ia1)*(N2/N1)*E1 //since E=Ke*Ia*N
+Rb=E2/Ia2-(Ra+Rs) //since E2=Ia2(Rb+Ra+Rs) during braking
+
+//Results
+mprintf("\n Braking current Ia2: %.1f A",Ia2)
+mprintf("\n Required braking resistance Rb: %.2f ohm",Rb)