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diff --git a/1938/CH3/EX3.10/3_10.sce b/1938/CH3/EX3.10/3_10.sce
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+clc,clear
+printf('Example 3.10\n\n')
+
+motor_output_FL =15000 //full load motor output
+V=250,R_sh=100
+
+//at 80 % of full load
+motor_output_FL_dash=(80/100)*motor_output_FL  //80 percent of full load output
+eta=90/100 //efficiency
+motor_input=motor_output_FL_dash/eta
+total_losses = motor_input - motor_output_FL_dash   //at 80 % of full load
+//at maximum efficiency , variable losses = constant losses
+constant_losses= total_losses/2
+variable_losses= constant_losses
+I= motor_input/V //line current at 80% load
+I_sh= V/ R_sh
+I_a= I- I_sh
+//since armature copper loss =R_a*I_a^2  
+R_a=variable_losses/I_a^2
+E_b1=V-I_a*R_a //motor back EMF at 80% of full load
+N_1=750 // corresponding speed is given as 750 rpm
+
+//When motor current is 80 A
+I=80
+I_a=I-I_sh
+arm_cu_losses= R_a*I_a^2  //armature copper loss
+total_losses =  arm_cu_losses + constant_losses
+motor_input= V*I
+motor_output = motor_input- total_losses
+eta=100*motor_output/motor_input //efficiency of motor
+printf('Efficiency of motor is %.2f percent when motor draws 80A current',eta)
+E_b2=V-I_a*R_a //motor back EMF at 80% of full load
+N_2=N_1*(E_b2/E_b1)  //because E_b is proportional to N
+printf('\nand Speed is %.2f r.p.m',N_2)