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+// A Texbook on POWER SYSTEM ENGINEERING
+// A.Chakrabarti, M.L.Soni, P.V.Gupta, U.S.Bhatnagar
+// DHANPAT RAI & Co.
+// SECOND EDITION
+
+// PART IV : UTILIZATION AND TRACTION
+// CHAPTER 1: INDUSTRIAL APPLICATIONS OF ELECTRIC MOTORS
+
+// EXAMPLE : 1.17 :
+// Page number 699
+clear ; clc ; close ; // Clear the work space and console
+
+// Given data
+hp = 50.0 // DC shunt motor rating(hp)
+V = 440.0 // Voltage(V)
+I_b = 150.0 // Breaking current(A)
+N_reduce = 40.0 // Speed of motor fallen by(%)
+R_a = 0.1 // Armature resistance(ohm)
+I_a_fl = 100.0 // Full-load armature current(A)
+N_fl = 600.0 // Full-load speed(rpm)
+
+// Calculations
+E_b = V-I_a_fl*R_a // Back emf of motor(V)
+V_a = V+E_b // Voltage across armature when braking starts(V)
+R_b = V_a/I_b // Resistance required(ohm)
+R_extra = R_b-R_a // Extra resistance required(ohm)
+T_fl = hp*746*60/(2*%pi*N_fl) // Full-load torque(N-m)
+T_initial_b = T_fl*I_b/I_a_fl // Initial breaking torque(N-m)
+E_b2 = E_b*(100-N_reduce)/100 // Back emf at new speed(V)
+I = (V+E_b2)/R_b // Current(A)
+EBT = T_fl*I/I_a_fl // Torque when motor speed reduced by 40%(N-m)
+
+// Results
+disp("PART IV - EXAMPLE : 1.17 : SOLUTION :-")
+printf("\nBraking torque = %.1f N-m", T_initial_b)
+printf("\nTorque when motor speed has fallen, E.B.T = %.1f N-m\n", EBT)
+printf("\nNOTE: ERROR: Calculation mistakes in the textbook solution")