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+// Example 11.7
+// Computation of the resistance of a dynamic braking resistor that will be
+// capable of developing 500 lb-ft of braking torque at a speed of 1000 r/min.
+// Page No. 464
+
+clc;
+clear;
+close;
+
+// Given data
+T1=910; // Torque load
+Pshaft=199.257*746; // Power of shaft
+eeta=0.940; // Efficiency
+VT=240; // Rated voltage
+T2=500; // Braking torque
+n1=1000; // Windage and friction speed
+n2=1150; // Speed of motor
+Rf=52.6; // Field resistance
+Racir=0.00707; // Combined armature,compensating winding and // interpolar resistance
+
+// Resistance of a dynamic braking resistor
+Pshaft=T1*n2/5252; // Shaft power
+Pin=Pshaft*746/eeta; // Input power
+IT=Pin/VT; // Total current
+If=VT/Rf; // Field current
+Ia1=IT-If; // Armature current
+Ea1=VT-Ia1*Racir; // Armature emf
+
+Ia2=Ia1*T2/T1; // Armature current
+Ea2=Ea1*n1/n2;
+RDB=(Ea2-Ia2*Racir)/Ia2; // Resistance
+
+//Display result on command window
+printf("\n Resistance of the dynamic braking resistor = %0.3f Ohm ",RDB);