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+{
+"cells": [
+ {
+		   "cell_type": "markdown",
+	   "metadata": {},
+	   "source": [
+       "# Chapter 1: Electric Drives"
+	   ]
+	},
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.10: Find_the_Value_of_speed_and_torque.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:1.10\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"V=230;//in volts\n",
+"I_1=90;//in amperes\n",
+"R_a=0.08;//in ohms\n",
+"R_se=0.05;//in ohms\n",
+"R_m=R_a+R_se;//in ohms\n",
+"R=1.5;//in ohms\n",
+"E_b1=V-I_1*(R_m+R);//in volts\n",
+"E_2=180;//in volts\n",
+"N2=700;//in rpm\n",
+"N1=N2*(E_b1/E_2);\n",
+"disp(ceil(N1),'Speed (in rpm)=');\n",
+"T=9.55*E_b1*I_1/N1;\n",
+"disp(T,'Torque (in Newton-meter)=')"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.12: Find_the_Value_of_torque_developed_and_terminal_voltage.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:1.12\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"P=4;//no. of poles\n",
+"f=50;//in hertz\n",
+"N_s=120*f/P;//in rpm\n",
+"V=400/sqrt(3);//in volts\n",
+"R2=4;//in ohms\n",
+"R1=1.5;//in ohms\n",
+"X1=4;//in ohms\n",
+"X2=4;//in ohms\n",
+"N=1350;//in rpm\n",
+"s=(N_s-N)/N_s;//slip\n",
+"T=(3*V^2*4/s)/((((R1+(R2/s))^2)+((X1+X2)^2))*(2*%pi*N_s/60));//in newton-meter\n",
+"N1=900;//in rpm\n",
+"s1=(N_s-N1)/N_s;//slip\n",
+"T1=T*(N1/N)^2;\n",
+"disp(T1,' Torque developed (in Newton-meter)=');\n",
+"V1=V*sqrt((N1/N)^2*(s1/s)*((((R1+(R2/s1))^2)+((X1+X2)^2)))/(((R1+(R2/s))^2)+((X1+X2)^2)));\n",
+"disp(V1,'Terminal Voltage (in volts)=');\n",
+"//Answer given in the textbook is worng as the torque equation is not multiplied by R2\n",
+"disp('Answer given in the textbook is worng as the torque equation is not multiplied by R2')"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.13: Find_the_Value_of_rms_voltage.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:1.13\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"P=4;//no. of poles\n",
+"f=50;//in hertz\n",
+"N_s=120*f/P;//in rpm\n",
+"s_f=0.05;//slip\n",
+"N=N_s*(1-s_f);//in rpm\n",
+"V=415;//in volts\n",
+"s_m=0.1;//slip corresponding to maximum slip\n",
+"N1=1350;//in rpm\n",
+"s_fn=(N_s-N1)/N_s;//full load slip\n",
+"V1=V*sqrt((N1/N)*(s_f/s_m)*(8/5));\n",
+"disp(V1,' RMS Voltage (in volts)=')"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.14: Find_the_Value_of_Slip_Frequency.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:1.14\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"f1=2;//in hertz\n",
+"f=50;//in hertz\n",
+"s_m=0.1;\n",
+"V=400;//in volts\n",
+"s1=0.04;//slip\n",
+"s2=(0.2095-sqrt((0.2095)^2-s1))/2;\n",
+"f_n=s2*40;\n",
+"disp(f_n,'Slip Frequency (in Hertz)=')"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.15: Find_the_Value_of_maximum_torque_at_one_half_load_and_25Hz_frequency.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:1.15\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"R1=0.02;//in ohms\n",
+"X1=0.1;//in ohms\n",
+"X2=X1;//in ohms\n",
+"//T_ratio is defined as the ratio of maximum torque at one-half load and 25Hz frequency to maximum torque at rated voltage and frequency\n",
+"T_ratio=(R1+sqrt(R1^2+(X1+X2)^2))/(2*(R1+sqrt(R1^2+((X1+X2)^2)/4)));\n",
+"disp(T_ratio,'   maximum torque at one-half load and 25Hz frequency =');\n",
+"disp('   times the maximum torque at rated voltage and frequency (T_max)');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.16: EX1_16.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:1.16\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"s_f=0.04;//full load slip\n",
+"I_ratio=6;//Ratio of Starting current to full load current\n",
+"T_ratio=I_ratio^2*s_f;//Ratio of Starting torque to full load torque\n",
+"disp(T_ratio,'(a) Starting Torque =');\n",
+"disp('   times the full load torque (T_f)');\n",
+"s_max=sqrt((I_ratio^2-1)/(625-I_ratio^2));\n",
+"disp(s_max,'(b) Slip at which Maximum torque occurs=');\n",
+"T_rm=(1/2)*((s_f/s_max)+(s_max/s_f));\n",
+"disp(T_rm,'(c) Ratio of maximum torque to full load torque=');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.17: Find_the_value_of_starting_torque.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:1.17\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"I_ratio=8;//Ratio of short circuit current to full load current\n",
+"s_f=0.04;//full load slip\n",
+"T_r1=I_ratio^2*s_f;\n",
+"disp(T_r1,'(a) Sarting Torque when started by means of direct switching=');\n",
+"disp('   times the full load torque');\n",
+"T_r2=I_ratio^2*s_f/3;\n",
+"disp(T_r2,'(b) Sarting Torque when started by star-delta starter=');\n",
+"disp('   times the full load torque');\n",
+"K=sqrt(3/8);// transformation ratio of transformer\n",
+"T_st=K^2*I_ratio^2*s_f;\n",
+"disp(T_st,'(C) Starting Torque =');\n",
+"disp('   times the full load torque');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.18: Find_the_value_of_ratio_of_starting_current_to_full_load_current.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:1.18\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"P=10*7355;//in watts\n",
+"V=400;//in volts\n",
+"pf=0.8//power factor\n",
+"Eff=0.9;//efficiency in per unit\n",
+"I_f=P/(sqrt(3)*V*pf*Eff);//in amperes\n",
+"I_sc=7.2;//in amperes\n",
+"I_sc1=I_sc*400/160;//in amperes\n",
+"I_st=I_sc1/3;//Starting current (in amperes)\n",
+"I_r=I_st/I_f;\n",
+"disp(I_r,'Ratio of starting current to full load current=')"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.19: EX1_19.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:1.19\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"P_o=50*1000;//in VA\n",
+"s_f=0.05;//slip\n",
+"V=400;//in volts\n",
+"I_f=P_o/(sqrt(3)*V);//in amperes\n",
+"Z=0.866;//in ohms/phase\n",
+"I_sc=V/(sqrt(3)*Z);//Short Circuit current (in amperes)\n",
+"I_st=100;//Supply current at start (in amperes)\n",
+"K=sqrt(I_st/I_sc);\n",
+"disp(K*100,'Tap Position of auto transformer(in %)=');\n",
+"I_ratio=I_sc/I_f;\n",
+"T_r=K^2*I_ratio^2*s_f;\n",
+"disp(T_r,'Ratio of Starting torque to full load torque =');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.1: Compare_the_annual_cost_of_a_group_drive_and_an_individual_drive.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:1.1\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"C_g=60000;//in Rs\n",
+"D=0.12*C_g;//in Rs\n",
+"E_c=75000;//in kWh\n",
+"C_e=4*E_c;//in Rs\n",
+"C_t=D+C_e;//in Rs\n",
+"C_id=18750*10;//in Rs\n",
+"AD=0.15*C_id;//in Rs\n",
+"E_a=60000;//in kWh\n",
+"C_ea=4*E_a;//in Rs\n",
+"C_total=AD+C_ea;//in Rs\n",
+"disp(C_t,'Total annual cost in case of group drive (in Rs)=');\n",
+"disp(C_total,'Total annual cost in case of individual drive (in Rs)=');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.20: EX1_20.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:1.20\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"V=440/sqrt(3);//in volts\n",
+"R_s=2;//in ohms\n",
+"R_r=2;//in ohms\n",
+"f=50;//in hertz\n",
+"X_s=3;//in ohms\n",
+"P=4;//no. of poles\n",
+"X_r=3;//in ohms\n",
+"R_o1=R_s+R_r;//Equivalent resistance of motor as referred to stator (in ohms)\n",
+"X_o1=X_s+X_r;////Equivalent reactance of motor as referred to stator (in ohms)\n",
+"I_st=V/(sqrt(R_o1^2+X_o1^2));//Starting current (in amperes)\n",
+"P_cu=3*I_st^2*R_r;//Copper loss (in watts)\n",
+"P2=7446;//in watts\n",
+"N_s=120*f/P;//Synchronous Speed (in rpm)\n",
+"T_st=9.55*P2/N_s;//Starting Torque (in Newton-meter)\n",
+"disp(I_st,'Starting Current of motor at 50 Hertz (in amperes)=');\n",
+"disp(T_st,'Starting Torque of motor at 50 hertz (in Newton-meters)=');\n",
+"V1=V*10/50;//in volts\n",
+"X_o2=X_o1*10/50;//in ohms\n",
+"I_st1=V1/(sqrt(R_o1^2+X_o2^2));//Starting current (in amperes)\n",
+"P_2=3*I_st1^2*R_r;//Copper loss (in watts)\n",
+"N_s1=120*10/P;//Synchronous Speed (in rpm)\n",
+"T_st2=9.55*P_2/N_s1;//Starting Torque (in Newton-meter)\n",
+"disp(I_st1,'Starting Current of motor at 10 Hertz (in amperes)=');\n",
+"disp(T_st2,'Starting Torque of motor at 10 hertz (in Newton-meters)=');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.21: Find_the_value_of_moment_of_inertia_of_drive.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:1.21\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"T_m=100;//Motor Torque (in Newton-meter)\n",
+"T_l=30;//Load Torque (in Newton-meter)\n",
+"alpha=2*%pi*10;//in angular acceleration (in rad/sec^2)\n",
+"J=(T_m-T_l)/alpha;\n",
+"disp(J,'Moment of inertia of drive (in Kg-m^2)')"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.22: Find_the_value_of_Time_in_attaining_full_load_speed.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:1.22\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"P_o=37.5*1000;//in watts\n",
+"N=500;//in rpm\n",
+"T_l=P_o*60/(2*%pi*N);//Full load  torque (in Newton-meter)\n",
+"T_st=(1.1+1.4)*T_l/2;// Average Starting Torque (in Newton-meters)\n",
+"T_a=T_st-T_l;//total available torque for acceleration\n",
+"J=20;//Moment of Inertia (in Kg-m^2)\n",
+"t1=J*2*%pi*N/(60*T_a);\n",
+"disp(t1,'Time in attaining full load speed (in seconds)=')"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.23: Find_the_value_of_starting_period.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:1.23\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"P_o=37.5*1000;//in watts\n",
+"N=500;//in rpm\n",
+"T_l=P_o*60/(2*%pi*N);//Full load  torque (in Newton-meter)\n",
+"T_m=2*T_l;// Torque developed by motor during starting\n",
+"T_a=T_m-T_l;//total available torque for acceleration\n",
+"E=37.5*660*9.81;//Stored energy of machine\n",
+"J=E*2/(2*%pi*N/60)^2;//Moment of inertia (in Kg-m^2)\n",
+"alpha=T_a/J;//angular acceleration (in rad/sec^2)\n",
+"t=(2*%pi*N/60)/alpha;\n",
+"disp(t,'Starting Period (in seconds)=')"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.24: Find_the_value_of_energy_dissipated.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:1.24\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"V=220;//in volts\n",
+"I=20;//in ampers\n",
+"R=1;//in ohms\n",
+"P_o=V*I-I^2*R;//Motor Output (in watts)\n",
+"w=200;//in radians/second\n",
+"T_l=P_o/w;//Load Torque (in N-m)\n",
+"J=5;//kg-m^2\n",
+"t_st=2.5;//in seconds\n",
+"alpha=w/t_st;//angular acceleration (in rad/second^2)\n",
+"K=(J*alpha+T_l)/I^2;\n",
+"W_st=(J*R*w/K)+(T_l*R*t_st/K);\n",
+"disp(W_st,'Energy Dissipated (in watts)=')"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.25: Find_the_value_of_additional_resistance.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:1.25\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"I_l1=22;//in amperes\n",
+"V=220;//in volts\n",
+"R_sh=100;//in ohms\n",
+"R_a=0.1;//in ohms\n",
+"I_sh=V/R_sh;//in amperes\n",
+"I_a1=I_l1-I_sh;//armatur current (in amperes)\n",
+"E_b1=V-I_a1*R_a;//Back Emf (in volts)\n",
+"N1=1000;//in rpm\n",
+"I_a2=0.8*19.8;//in amperes\n",
+"R=(218.416-(800*218.02/1000))/I_a2;\n",
+"disp(R,'Value of additional resistance (in ohms)=');\n",
+"I_a3=0.64*I_a1;//in amperes\n",
+"R3=(218.7328-(800*218.02/1000))/I_a3;\n",
+"disp(R3,'Value of additional resistance (in ohms)=');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.26: Find_the_value_of_additional_resistance.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:1.26\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"I_1=50;//in amperes\n",
+"V=500;//in volts\n",
+"N_ratio=0.5;//Speed Ratio\n",
+"E_b1=V;//Back Emf (in volts)\n",
+"T_ratio=N_ratio^3;//Torque ratio\n",
+"I_2=I_1*sqrt(T_ratio);//in amperes\n",
+"R=(E_b1-(I_2*N_ratio*E_b1/I_1))/I_2;\n",
+"disp(R,'Value of additional resistance (in ohms)=');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.27: Find_the_value_of_diverter_resistance.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:1.27\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"N_ratio=1.2;//Speed Ratio\n",
+"//From Saturation Curve\n",
+"I_ratio=0.65;//feild current ratio corresponding to 83.3% of full load value of flux to 65% of full load value of flux\n",
+"I_a_ratio=N_ratio;//Armature current ratio corresponding to 83.3% of full load value of flux to 65% of full load value of flux\n",
+"R_ratio=I_ratio/(I_a_ratio-I_ratio);\n",
+"disp(R_ratio,'Value of Diverter resistance (in ohms)=');\n",
+"disp('   times the Series Feild Resistance (R_se)')"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.28: Find_the_value_of_Armature_Current_at_1000_rpm.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:1.28\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"I_ab=800;//Armature current (in amperes)\n",
+"N1=1000;//in rpm\n",
+"N2=500;//in rpm\n",
+"I=I_ab*N1/N2;\n",
+"disp(I,' Armature Current at 1000 rpm (in amperes)=')"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.29: Find_the_value_of_additional_resistance.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:1.29\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"f=50;//in hertz\n",
+"P=4;//No.of poles\n",
+"N_s=120*f/P;//Synchronous Speed (in rpm)\n",
+"N=1440;//Full load speed (in rpm)\n",
+"s1=(N_s-N)/N_s;//Full load Slip\n",
+"N2=1200;//in rpm\n",
+"s2=(N_s-N2)/N_s;//slip\n",
+"R2=0.25;//ohms per phase\n",
+"R=(s2*R2/s1)-R2;\n",
+"disp(R,'Value of additional resistance (in ohms)=');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.2: Find_the_value_of_stable_operating_point.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exam:1.2\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"a=1;\n",
+"b=1;\n",
+"c=-30;\n",
+"w_m=(-b+sqrt((b^2)-4*a*c))/(2*a);//speed of the drive\n",
+"t_l=0.5*(w_m^2);//motoring torqe \n",
+"disp(t_l,w_m,'stable operating point=');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.30: Find_the_value_of_frequecncy_of_rotor_currents_and_slip.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:1.30\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"f=50;//in hertz\n",
+"P1=6;//No. of poles\n",
+"P2=4;//No.of poles\n",
+"N_sc=120*f/(P1+P2);//Synchronous Speed (in rpm)\n",
+"s=0.02;//slip\n",
+"N=N_sc*(1-s);//Actual Speed (in rpm)\n",
+"N_s=120*f/P1;//Synchronous Speed of 6-pole motor\n",
+"s1=(N_s-N)/N_s;\n",
+"f1=s1*f;\n",
+"disp(f1,'Frequency of rotor current of 6-pole motor (in Hertz)=');\n",
+"disp(s1,'Slip reffered to 6-pole stator feild=');\n",
+"N_s2=120*f1/P2;//Synchronous Speed of 4-pole motor\n",
+"s2=(N_s2-N)/N_s2;\n",
+"f2=s2*f1;\n",
+"disp(f2,'Frequency of rotor current of 4-pole motor (in Hertz)=');\n",
+"disp(s2,'Slip reffered to 4-pole stator feild=');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.31: EX1_31.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:1.31\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"f=50;//in hertz\n",
+"P1=6;//No. of poles\n",
+"P2=4;//No.of poles\n",
+"N_s1=120*f/P1;//Synchronous Speed of 6-pole motor\n",
+"N_s2=120*f/P2;//Synchronous Speed of 4-pole motor\n",
+"N_sc1=120*f/(P1+P2);//Concantenated Speed of set when cumulatively compounded (in rpm)\n",
+"N_sc2=120*f/(P1-P2);//Concantenated Speed of set when differentially compounded (in rpm)\n",
+"disp(' Available Speeds (in rpm) are :');\n",
+"disp(N_s1,'');\n",
+"disp(N_s2,'');\n",
+"disp(N_sc1,'');\n",
+"disp(N_sc2,'');\n",
+"P_o=15;//in HP\n",
+"disp(P_o,'Maximum Load which can be delievered (in HP)=');\n",
+"r=P1/P2;\n",
+"disp(r,'Ratio of Mechanical Power Output')"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.32: Find_the_value_of_Resistance_to_be_added_to_each_slip_ring.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:1.32\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"f=50;//in hertz\n",
+"V=440;//in volts\n",
+"P_o=110*1000;//in watts\n",
+"P=24;//No.Of Poles\n",
+"N_s=120*f/P;//Synchronous Speed (in rpm)\n",
+"N=245;//in rpm\n",
+"s_f=(N_s-N)/N_s;//Full load Speed\n",
+"T_f=P_o/(2*%pi*N/60);//Full load Torque (in N-m)\n",
+"R=0.04;//in ohms\n",
+"R2=R/2;//Rotor resistance per phase (in ohms)\n",
+"K=1.25;// ratio of stator turns to rotor turns\n",
+"R_2=R2*K^2;//Rotor resistance reffered to stator (in ohms)\n",
+"X_2=sqrt(((V^2*R_2*1.2/(T_f*500*%pi))-R_2^2)*(1/R2)^2);//in ohms\n",
+"s=(N_s-175)/N_s;//slip at 175 rpm\n",
+"T=T_f*175^2/N^2;//Torque at 175 rpm (in N-m)\n",
+"b=-(V^2*s*60/(T*2*%pi*N_s));\n",
+"a=1;\n",
+"c=(s*X_2)^2;\n",
+"R_n=(-b+sqrt(b^2-4*a*c))/(2*a)\n",
+"R_ext=(R_n-R_2)/K^2;\n",
+"disp(R_ext,'Resistance to be added to each slip ring (in ohms)=')"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.33: EX1_33.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:1.33\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"I_f=100;//in amperes\n",
+"V=220;//in volts\n",
+"N=1000;//in rpm\n",
+"T_f=V*I_f/(2*%pi*N/60);//Full load torque (N-m)\n",
+"E_bf=V;//Back emf (in volts)\n",
+"V_a=V+E_bf;// Voltage across armature (in volts)\n",
+"I_b=2*I_f;//braking current\n",
+"R=(V_a/I_b);//in ohms\n",
+"disp(R,'Value of external resistance (in ohms)=');\n",
+"T_b=T_f*I_b/I_f;\n",
+"disp(T_b,'Initial Braking Torque (in N-m)=');\n",
+"E_b1=E_bf*500/N;//in volts\n",
+"I_b1=(V+E_b1)/R;//in amperes\n",
+"T_b1=T_f*I_b1/I_f;\n",
+"disp(T_b1,'Braking Torque when speed reduced to 500 rpm (in N-m)=');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.34: Find_the_value_of_resistance_and_breaking_torque.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:1.34\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"P_o=17.6*1000;//in watts\n",
+"Eff=0.8;//Efficiency\n",
+"V=220;//in volts\n",
+"I_f=P_o/(V*Eff);//in amperes\n",
+"I_af=I_f;//in amperes\n",
+"R_a=0.1;//in ohms\n",
+"N=1200;//in rpm\n",
+"T_f=P_o/(2*%pi*N/60);//Full load torque (N-m)\n",
+"E_bf=V-I_af*R_a;//Back emf (in volts)\n",
+"V_a=V+E_bf;// Voltage across armature (in volts)\n",
+"I_b=2*I_f;//braking current\n",
+"R=(V_a/I_b)-R_a;//in ohms\n",
+"disp(R,'Value of external resistance (in ohms)=');\n",
+"E_b1=E_bf*400/N;//in volts\n",
+"I_b1=(V+E_b1)/(R+R_a);//in amperes\n",
+"T_b1=T_f*I_b1/I_f;\n",
+"disp(T_b1,'Braking Torque when speed reduced to 400 rpm (in N-m)=');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.35: EX1_35.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:1.35\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"V=220;//in volts\n",
+"P_o=400*9.81*2.5;//(in watts)\n",
+"Eff=0.85;//efficiency of motor\n",
+"Eff_h=0.8\n",
+"P_in=P_o/(Eff*Eff_h);//in watts\n",
+"I=P_in/V;//in amperes\n",
+"disp(I,'Current Drawn (in amperes)=');\n",
+"P_out=P_o*Eff*Eff_h;//in watts\n",
+"R=V^2/P_out;\n",
+"disp(R,'Value of additional resistance (in ohms)=')"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.36: Find_the_value_of_Current_Drawn_and_Value_of_additional_resistance.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:1.36\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"T=245;//in N-m\n",
+"N=250;//in rpm\n",
+"P_in=T*2*%pi*N/60;//in watts\n",
+"//Corresponding to the value of P_in we found I=27.5A and E=233 V from the given curve shown in fig.1.102\n",
+"E=233;//in volts\n",
+"I=27.5;//in amperes\n",
+"r=E/I;//resistance of the circuit\n",
+"R=r-1;//External Resistance to be inserted (in ohms)\n",
+"disp(R,'External Resistance to be inserted (in ohms)=')"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.37: Find_the_value_of_speed_under_regenerative_braking_plugging_and_dynamic_braking.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:1.37\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"P_o=45*1000;//in watts\n",
+"R_a=0.2;//in ohms\n",
+"V=500;//in volts\n",
+"Eff=0.9;//Efficiency\n",
+"I_lf=P_o/(V*Eff);//Rated Line current (in amperes)\n",
+"R_sh=200;//in ohms\n",
+"I_sh=V/R_sh;//Shunt feild Current (in amperes)\n",
+"I_af=I_lf-I_sh;//Armature current on full load (in Amperes)\n",
+"E_f=V-I_af*R_a;//emf induced (in volts)\n",
+"N_f=600;//in rpm\n",
+"E1=V+I_af*R_a;//in volts\n",
+"N1=E1*N_f/E_f;\n",
+"disp(N1,'Speed under regenerative braking(in rpm)=');\n",
+"E2=I_af*(5.5+R_a)-V;//in volts\n",
+"N2=E2*N_f/E_f;\n",
+"disp(N2,'Speed under plugging (in rpm)=');\n",
+"E3=I_af*(2.6+R_a);//in volts\n",
+"N3=E3*N_f/E_f;\n",
+"disp(N3,'Speed under dynamic braking(in rpm)=');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.38: Find_the_value_of_speed.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:1.38\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"V=230;//in volts\n",
+"I_a=100;//in amperes\n",
+"R_a=0.05;//in ohms\n",
+"E_b=V-I_a*R_a;//in volts\n",
+"N=870;//in rpm\n",
+"T=E_b*I_a/(2*%pi*N/60);//torque developed (in N-m)\n",
+"T_l=400;//in N-m\n",
+"I_an=I_a*T_l/T;//in amperes\n",
+"E=V+I_an*R_a;//in volts\n",
+"N1=N*E/230;\n",
+"disp(N1,'Speed (in rpm)=')"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.39: Find_the_reduction_in_flux_and_motor_speed.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:1.39\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"I_a1=100;//in Amperes\n",
+"V=230;//in volts\n",
+"R_a=0.1;//in ohms\n",
+"E_b1=V-I_a1*R_a;//in volts\n",
+"N1=500;//in rpm\n",
+"N2=800;//in rpm\n",
+"x=(V-sqrt((V^2)-4*10*352))/(2*10);\n",
+"disp('Flux is reduced by');\n",
+"disp(x^-1,);\n",
+"disp('times to get motor speed of 800 rpm');\n",
+"I_a2=I_a1*x;//in amperes\n",
+"E_b2=V-I_a2*R_a;//in volts\n",
+"T_2=E_b2*I_a2*60/(2*%pi*N2);//in N-m\n",
+"T_3=800;//in N-m\n",
+"I_a3=I_a2*T_3/T_2;//in Amperes\n",
+"E_b3=V+I_a3*R_a;//in amperes\n",
+"N3=E_b3*N2/E_b2;\n",
+"disp(ceil(N3),'Speed (in rpm)=');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.3: Find_the_value_of_moment_of_inertia_and_power_developed.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exam:1.2\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"J_m=0.4;//motor inertia(in Kg-m2)\n",
+"J_l=10;//load inertia(in Kg-m2)\n",
+"a=0.1;//Teeth ratio of gear\n",
+"i=1/a;\n",
+"N=1400;\n",
+"pi=22/7;\n",
+"n=0.90;//efficency of motor\n",
+"T_l=50;//Torque(N-m)\n",
+"J=J_m+J_l/(i^2);//Total moment of inertia referred to the motor shaft\n",
+"T_L=T_l/(i*n);//total equivalent torque referref to motor shaft\n",
+"P=T_L*2*pi*N/60;//power developed by motor\n",
+"disp(ceil(P),'power developed by motor(in Watt)=');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.40: Find_the_value_of_plugging_torque.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:1.40\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"f=50;//in hertz\n",
+"P=4;//Number of poles\n",
+"N_s=120*f/P;//Synchronous Speed (in rpm)\n",
+"s_f=0.05;//Full load Slip\n",
+"N_f=N_s*(1-s_f);//Full load speed (in rpm)\n",
+"P_d=30*1000;//in watts\n",
+"T_f=P_d/(2*%pi*N_f/60);//In N-m\n",
+"s_2=2-s_f;//Slip at plugging\n",
+"T_p=(s_2/s_f)*T_f*(1+16*s_f^2)/(1+16*s_2^2);\n",
+"disp(T_p,'Plugging Torque (in N-m)=')"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.41: EX1_41.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:1.41\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"R2=0.5;//in ohms\n",
+"X2=2.4;//in ohms\n",
+"a=0.5;//ratio\n",
+"s_f=0.05;//slip\n",
+"f=50;//in hertz\n",
+"P=8;//Number of Poles\n",
+"R_2=R2*a^2;//in ohms\n",
+"X_2=X2*a^2;//in ohms\n",
+"s=2-s_f;//Slip during Plugging\n",
+"N_s=120*f/P;//in rpm\n",
+"V=400/sqrt(3);//in volts\n",
+"R_L=2;//in ohms\n",
+"R_1=0.1;//in ohms\n",
+"X_1=0.6;//in ohms\n",
+"I_2=V/sqrt(((R_1+(R_2+R_L)/s)^2)+(X_1+X_2)^2);//in amperes\n",
+"T_b=3*60*I_2^2*(R_2+R_L)/(2*%pi*N_s*s);\n",
+"disp(int(T_b),'Initial Braking Torque (in N-m)=');\n",
+"E_2=V*sqrt(((R_2/s_f)^2+(X_2^2))/(((R_2/s_f)+R_1)^2)+1.2^2)/sqrt(3);\n",
+"S=1-s_f;//Slip during breaking\n",
+"I_2b=E_2/sqrt((X_2^2)+((R_L+R_2)/S)^2);\n",
+"T_bn=3*60*I_2b^2*(R_2+R_L)/(2*%pi*N_s*S);\n",
+"disp(T_bn,'Initial Braking Torque during dc dynamic braking(in N-m)=');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.42: EX1_42.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:1.42\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"J=630;//in kg-m^2\n",
+"T_f=1.4*9.81;//in N-m\n",
+"T_e=165*9.81;//in N-m\n",
+"T_b=T_e+T_f;//in N-m\n",
+"Beta=T_b/J;//in rad/sec^2\n",
+"f=50;//in hertz\n",
+"P=8;//no of poles\n",
+"N_s=120*f/P;//in rpm\n",
+"w_1=2*%pi*N_s/60;//in rad/sec\n",
+"t=w_1/Beta;\n",
+"disp(t,'Time taken to stop the motor (in seconds)=');\n",
+"n=w_1^2/(2*%pi*Beta*2);\n",
+"disp(n,'Number of revolutions made=');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.43: Find_the_value_of_time_taken_and_number_of_revolutions.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:1.43\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"P_o=37.5*1000;//in Watts\n",
+"N=750;//in rpm\n",
+"Eff=0.9;//Efficiency\n",
+"V_L=400;//in Volts\n",
+"pf=0.85;//Power Factor\n",
+"R_b=2.5;//in ohms\n",
+"T_f=P_o*60/(2*%pi*N);//in N-m\n",
+"I_L=P_o/(sqrt(3)*V_L*pf*Eff);//in Amperes\n",
+"I_b=V_L/(sqrt(3)*R_b);//in Amperes\n",
+"T_E=T_f*I_b/I_L;//in N-m\n",
+"T_i_total=T_f+T_E;//in N-m\n",
+"w=2*%pi*N/60;//in rad/sec\n",
+"K=T_E/w;\n",
+"J=20;//kg-m^2\n",
+"t=(J/K)*log((T_f+K*w)/T_f);\n",
+"disp(t,'Time taken (in Seconds)=');\n",
+"n=(1/(2*%pi*K))*(((J/K)*(T_f+K*w)*(1-exp(-K*t/J)))-T_f*t);\n",
+"disp(n,'Number of Revolutions Made=')"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.44: Find_the_value_of_time_taken.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:1.44\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"E=240;//in volts\n",
+"R=15;//in ohms\n",
+"N=1500;//in rpm\n",
+"P=E^2/R;//in Watts\n",
+"T_b=P*60/(2*%pi*N);//in N-m\n",
+"T_e=T_b;\n",
+"w_1=2*%pi*N/60;//in rad/sec\n",
+"K=T_e/w_1;\n",
+"J=20;//kg-m^2\n",
+"t=(J/K)*log(w_1/62.832);\n",
+"disp(t,'Time taken to bring motor from 1500 rpm to 600 rpm (in seconds)=');\n",
+"T_f=1.5*9.81;//in N-m\n",
+"t_o=(J/K)*log((T_f+T_e)/(T_f+(T_e*600/1500)));\n",
+"disp(t_o,'Time taken for fall of speed if there exist frictional torque (in seconds)=');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.45: Find_the_value_of_final_temperature_rise_and_heating_time_constant.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:1.45\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"d=0.65;//in meters\n",
+"l=1;//in meters\n",
+"P_o=12*735.5;//in watts\n",
+"Eff=0.9;//Efficiency\n",
+"P_in=P_o/Eff;//in watts\n",
+"P_L=P_in-P_o;//in watts\n",
+"m=400;//in kg\n",
+"C_p=700;//in J/Kg/Celcius\n",
+"alpha=12;//in watts/m^2/Celcius\n",
+"S=%pi*d*l;//in m^2\n",
+"Theta=P_L/(S*alpha);//in Celcius\n",
+"t=m*C_p/(S*alpha);\n",
+"disp(Theta,'Final temperatur rise (in degree celcius)=');\n",
+"disp(ceil(t),'Heating time constant (in seconds)=');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.47: EX1_47.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:1.47\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"theta_1=20;//in degree celcius\n",
+"theta_2=34;//in degree celcius\n",
+"t=-1/log((theta_2/theta_1)-1);//in hours\n",
+"disp(t,'Heating time constant (in hours)=');\n",
+"theta_F=theta_1/(1-exp(-1/t));\n",
+"disp(theta_F,'Final steady temperature rise (in degree celcius)=');\n",
+"theta_f=theta_F/(1-exp(-1/t));\n",
+"x=sqrt(2*(theta_f/theta_F)-1);\n",
+"disp('one hour rating of motor is');\n",
+"disp(x,'times full load rating');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.48: Find_the_half_hour_rating_of_the_motor.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:1.48\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"P=25;//in KW\n",
+"t=1.5;//in hours\n",
+"P_L=sqrt((((1/(1-exp(-0.5/t)))*1.9)-0.9)*P^2);\n",
+"disp(P_L,'Half hour rating of a 25KW Motor (in KW)=')"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.49: Find_the_running_time_of_the_motor.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:1.49\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"t=60;//in minutes\n",
+"theta_F=20;//in degree celcius\n",
+"P_L1=2.5625;//Total losses at P KW\n",
+"P_L2=7.25;//Total losses at 2P KW\n",
+"theta_f=theta_F*P_L2/P_L1;//in degree celcius\n",
+"t_o=t*log(1/(1-(theta_F/theta_f)));\n",
+"disp(t_o,'Time of operation (in minutes)=');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.4: Find_the_value_of_moment_of_inertia_and_power_developed.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exam:1.4\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"J_m=0.4;//motor inertia(in Kg-m2)\n",
+"J_l=10;//load inertia(in Kg-m2)\n",
+"a=0.1;//Teeth ratio of gear\n",
+"N=1500;\n",
+"pi=22/7;\n",
+"n_t=0.88;\n",
+"m=600;//weight\n",
+"g=9.81;\n",
+"f_r=m*g;//force\n",
+"w_m=fix(2*pi*N/60);//motor speed\n",
+"w=2;//uniform speed of weight lifting\n",
+"n=0.9;//efficency of motor\n",
+"T_l=50;//Torque(N-m)\n",
+"J=J_m+(a^2)*J_l+m*((w/w_m)^2);//Total moment of inertia referred to the motor shaft\n",
+"T_L=(a*T_l/n)+f_r*w/(n_t*w_m) ;//total equivalent torque referred to motor shaft\n",
+"p=T_L*w_m;//power developed by motor(in Watt)\n",
+"P=p/1000;//power developed by motor(in kWatt)\n",
+"disp(J,'Total torque referred to motor shaft(in kg-m2)=')\n",
+"disp(T_L,'Total equivalent Torque referred to motor shaft(in N-m)=')\n",
+"disp(P,'power developed by motor(in kWatt)=')"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.51: Find_out_the_continuous_rating_of_the_motor.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:1.51\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"Eff=0.8;//Efficiency\n",
+"P1=400;//in watts\n",
+"t1=60;//in minutes\n",
+"t2=15;//in minutes\n",
+"P=sqrt((((2.5625/(1-exp(-t2/t1)))-1)^(-1))*(P1/Eff)^2);\n",
+"disp(P,'Continuous Rating of Motor (in Watts)=');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.52: EX1_52.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:1.52\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"theta_1=50;//in degree Celcius\n",
+"theta_F=80;//in degree celcius\n",
+"t=0.75;//in hours\n",
+"theta=theta_F*(1-exp(-1/t));\n",
+"disp(theta_F,'Temperature rise after 1 hour (in degree celcius)=');\n",
+"theta_f=theta_F/(1-exp(-1/t));\n",
+"disp(theta_f,'Steady state temperature rise at 1 hour rating (in degree celcius)=');\n",
+"T=-t*log(1-(theta_1/theta_f));\n",
+"disp(60-T*60,'Time taken to increase temperature from 50 to 80 degree celcius (in minutes)=');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.53: Find_the_value_of_load.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:1.53\n",
+"clc;\n",
+"clear;\n",
+"P_cont=100;//in KWs\n",
+"Eff=0.8;//Efficiency\n",
+"T_1=50;//in minutes\n",
+"T_2=70;//in minutes\n",
+"t_1=10;//in minutes\n",
+"t_2=10;//in minutes\n",
+"r=(1-exp(-((t_1/T_1)+(t_2/T_2))))/(1-exp(-t_1/T_1));// r=theta_f/theta_F\n",
+"P_L=2.5625;//Losses at 100 KW Load \n",
+"P_L1=Eff*P_cont;//in Kws\n",
+"P=sqrt(((P_L*r)-1)*P_L1^2);\n",
+"disp(P,'Value of Load in KW during load period=');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.54: Find_the_value_of_final_temperature_rise_and_heating_time_constant.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:1.54\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"theta_1=20;//in degree celcius\n",
+"theta_2=30;//in degree celcius\n",
+"t_1=30;//in minutes\n",
+"t_2=60;//in minutes\n",
+"t=-(t_2-t_1)/log((theta_2/theta_1)-1);//in minutes\n",
+"theta_F=theta_1/(1-exp(-t_1/t));\n",
+"disp(t,'Heating Time Contant (in minutes)=');\n",
+"disp(theta_F,'Final Temperature Rise (in Degree Celcius)=');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.55: Find_the_value_of_maximum_overload.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:1.55\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"theta_1=30;//in degree celcius\n",
+"theta_2=40;//in degree celcius\n",
+"t_1=1;//in hours\n",
+"t_2=2;//in hours\n",
+"x=(theta_2/theta_1)-1;\n",
+"theta_F=theta_1/(1-x);//in degree celcius\n",
+"theta_f=50/(1-x);//in degree celcius\n",
+"P_L=25;//in KWs\n",
+"P=P_L*sqrt(theta_f/theta_F);\n",
+"disp(P,'Maximum Overload (in KWs)=')"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.56: Find_the_value_of_temperature_rise.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:1.56\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"theta_1=20;//in degree celcius\n",
+"theta_2=35;//in degree celcius\n",
+"t_1=1/2;//in hours\n",
+"t_2=1;//in hours\n",
+"t=-(t_2-t_1)/log((theta_2/theta_1)-1);//in minutes\n",
+"theta_F=theta_1/(1-exp(-t_1/t));\n",
+"theta=theta_F*(1-exp(-2/t));\n",
+"disp(theta,'Temperature Rise After 2 hrs (in Degree Celcius)=');\n",
+"theta_F1=theta_F*0.8;//in Degree Celcius\n",
+"t_o=0.8*t;//in hours\n",
+"theta_o=theta_F1*(1-exp(-1/t_o));\n",
+"disp(theta_o,'Temperature Rise from cold After 1 hr at full load (in Degree Celcius)=');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.57: Determine_the_suitable_size_of_continuously_rated_motor.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:1.57\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"P_1=100;//in KWs\n",
+"P_2=50;//in KWs\n",
+"t_1=10;//in minutes\n",
+"t_2=8;//in minutes\n",
+"t_3=5;//in minutes\n",
+"t_4=4;//in minutes\n",
+"P=sqrt(((t_1*P_1^2)+(t_2*P_2^2))/(t_1+t_2+t_3+t_4));\n",
+"disp(P,'Rating Of Continuously Rated Motor (in KWs)=');\n",
+"disp('Adequate rating of motor=70 Kws');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.58: Find_the_power_rating_of_the_motor.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:1.58\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"T_1=240;//in N_m\n",
+"T_2=140;//in N-m\n",
+"T_3=300;//in N-m\n",
+"T_4=200;//in N-m\n",
+"t_1=20;//in minutes\n",
+"t_2=10;//in minutes\n",
+"t_3=10;//in minutes\n",
+"t_4=20;//in minutes\n",
+"T=sqrt(((t_1*T_1^2)+(t_2*T_2^2)+(t_3*T_3^2)+(t_4*T_4^2))/(t_1+t_2+t_3+t_4));\n",
+"N=720;//in rpm\n",
+"P=T*2*%pi*N/60;\n",
+"disp(P,'Power rating of Motor(in KWs)=');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.59: Determine_the_kW_rating_of_the_motor.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:1.59\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"t=90;//in seconds\n",
+"T_eq=sqrt(40750/t);//in Kg-m\n",
+"N=750;//in rpm\n",
+"P=T_eq*9.81*2*%pi*N/60;\n",
+"disp(P,'Power Rating Of Motor (in Kws)=');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.5: Find_the_value_of_motor_speed.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:1.5\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"V=220;//in volts\n",
+"V_1=200;//in volts\n",
+"N=1000;//in rpm\n",
+"I=100;//in amperes\n",
+"R_a=0.1;//in ohms\n",
+"E_b=V-I*R_a;//in volts\n",
+"I_1=I;//in amperes\n",
+"E_b1=V_1-I_1*R_a;//in volts\n",
+"N_1=N*E_b1/E_b;\n",
+"disp(ceil(N_1),'Motor Speed (in rpm)=')"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.61: Find_the_value_of_speed_at_the_end_of_deceleration_period.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:1.61\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"T_l=100*9.81;//in N-m\n",
+"t=10;//in seconds\n",
+"J=1000;//kg-m^2\n",
+"f=50;//in hertz\n",
+"P=4;//no.of poles\n",
+"N_s=120*f/P;//synchronous speed (in rpm);\n",
+"s=0.06;//slip\n",
+"w_s=s*N_s*2*%pi/60;//slip speed (in rad/sec)\n",
+"K=w_s/(50*9.81);\n",
+"T_m=T_l-T_l*exp(-t/(K*J));\n",
+"N_sn=K*T_m*60/(2*%pi);//in rpm\n",
+"N=N_s-N_sn;\n",
+"disp(N,'Speed at the end of deceleration period (in rpm)=')"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.62: Determine_the_value_of_inertia_of_the_flywheel.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:1.62\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"P_o=500*735.5;//in watts\n",
+"N_o=40;//in rpm\n",
+"s_f=0.12;\n",
+"N_f=N_o*(1-s_f);//full load speed (in rpm)\n",
+"T_f=P_o/(2*%pi*N_f/60);//Full load torque (N-m)\n",
+"T_m=2*T_f;//Motor torque (in N-m)\n",
+"T_l=41500*9.81;//Load torque (in N-m)\n",
+"t=10;//seconds\n",
+"w_s=s_f*N_o*2*%pi/60;//slip speed (in rad/sec)\n",
+"K=w_s/T_f;\n",
+"J=-t/(K*log(1-(T_m/T_l)));\n",
+"disp(J,'Moment of Inertia (in Kg-m^2)=')"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.63: Find_the_value_of_weight_of_flywheel_and_time_taken.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:1.63\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"P_o=50*1000;//in watts\n",
+"f=50;//in hertz\n",
+"s_f=0.04;//slip\n",
+"P=6;//no.of poles\n",
+"N_s=120*f/P;//Synchronous Speed (in rpm)\n",
+"N_f=N_s*(1-s_f);\n",
+"T_f=P_o/(2*%pi*N_f)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.64: Find_the_value_of_moment_of_inertia.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:1.64\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"T_L=600;//in N-m\n",
+"T_m=450;//in N-m\n",
+"N=600;//in rpm\n",
+"w_o=2*%pi*N/60;//in rad/sec\n",
+"s=0.08;//slip\n",
+"w=s*w_o;//in rad/sec\n",
+"K=w/T_m;//Torque constant\n",
+"J=(-10/K)/log(0.25);//in Kg-m^2\n",
+"J_m=10;//in Kg-m^2\n",
+"J_F=J-J_m;\n",
+"disp(J_F,'Moment Of Inertia Of Flywheel (in Kg-m^2)=');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.65: Find_the_value_of_moment_of_inertia.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:1.45\n",
+"clc;\n",
+"clear;\n",
+"close;"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.6: Find_the_value_of_full_load_speed_and_full_load_torque.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:1.6\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"V=230;//in volts\n",
+"R_sh=230;//in ohms\n",
+"R_a=0.5;//in ohms\n",
+"I_sh=V/R_sh;//in amperes\n",
+"I_lo=3;//in amperes\n",
+"I_ao=I_lo-I_sh;//in amperes\n",
+"E_bo=V-I_ao*R_a;//in volts\n",
+"N_o=1000;//in rpm\n",
+"I_lf=23;//in amperes\n",
+"I_af=I_lf-I_sh;//in amperes\n",
+"E_bf=V-I_af*R_a;//in volts\n",
+"Phy_ratio=0.98;\n",
+"N_f=N_o*(E_bf/E_bo)/Phy_ratio;\n",
+"disp(ceil(N_f),'Full Load Speed (in rpm)=');\n",
+"T_f=9.55*E_bf*I_af/N_f;\n",
+"disp(T_f,'Full load Torque (in Newton-meter)=');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.7: Find_the_value_of_armature_voltage_drop_at_full_load.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:1.7\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"V=440;//in volts\n",
+"N_o=2000;//in rpm\n",
+"E_bo=440;//in volts\n",
+"N_f=1000;//in rpm\n",
+"N_h=1050;//in rpm\n",
+"E_bf=E_bo*N_f/N_o//in volts\n",
+"E_b=E_bo*N_h/N_o;//in volts\n",
+"v=(E_b-E_bf)*2;\n",
+"disp(v,'Armature voltage drop at full load (in volts)=')"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.8: Find_the_value_of_speed.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:1.8\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"V=230;//in volts\n",
+"N1=750;//in rpm\n",
+"R=10;//in ohms\n",
+"I_a=30;//in amperes\n",
+"N2=N1*((V+I_a*R)/V)^-1;\n",
+"disp(int(N2),'Speed (in rpm)=')"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.9: Find_the_value_of_speed.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:1.9\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"V=200;//in volts\n",
+"I_1=20//in amperes\n",
+"R_a=0.5;//in ohms\n",
+"E_b1=V-I_1*R_a;//in volts\n",
+"N1=700;//in rpm\n",
+"I_2=sqrt(1.44)*I_1;//in amperes\n",
+"E_b2=V-I_2*R_a;//in volts\n",
+"N2=N1*(E_b2/E_b1)*(I_1/I_2);\n",
+"disp(int(N2),'(a) Speed (in rpm)=');\n",
+"I_3=10;//in amperes\n",
+"E_b3=V-I_3*R_a;//in volts\n",
+"N3=N1*(E_b3/E_b1)*(I_1/I_3);\n",
+"disp(ceil(N3),'(b) Speed (in rpm)=');"
+   ]
+   }
+],
+"metadata": {
+		  "kernelspec": {
+		   "display_name": "Scilab",
+		   "language": "scilab",
+		   "name": "scilab"
+		  },
+		  "language_info": {
+		   "file_extension": ".sce",
+		   "help_links": [
+			{
+			 "text": "MetaKernel Magics",
+			 "url": "https://github.com/calysto/metakernel/blob/master/metakernel/magics/README.md"
+			}
+		   ],
+		   "mimetype": "text/x-octave",
+		   "name": "scilab",
+		   "version": "0.7.1"
+		  }
+		 },
+		 "nbformat": 4,
+		 "nbformat_minor": 0
+}
diff --git a/Elements_of_Electric_Drives_by_J_B_Gupta/3-Thyristor_Control_Of_Electric_Motors.ipynb b/Elements_of_Electric_Drives_by_J_B_Gupta/3-Thyristor_Control_Of_Electric_Motors.ipynb
new file mode 100644
index 0000000..068add6
--- /dev/null
+++ b/Elements_of_Electric_Drives_by_J_B_Gupta/3-Thyristor_Control_Of_Electric_Motors.ipynb
@@ -0,0 +1,833 @@
+{
+"cells": [
+ {
+		   "cell_type": "markdown",
+	   "metadata": {},
+	   "source": [
+       "# Chapter 3: Thyristor Control Of Electric Motors"
+	   ]
+	},
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.10: Find_the_value_of_no_load_speed_and_firing_angle.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:3.10\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"alpha_a=45;//in degrees\n",
+"R_a=0.2;//in ohms\n",
+"K=0.25;//in volts/rpm\n",
+"V=400;//in volts\n",
+"I_ao=5;//in amperes (no load armature current)\n",
+"N=1500;//in rpm\n",
+"I_a=100;//in amperes\n",
+"V_ao=3*sqrt(3)*V*sqrt(2)*(1+cosd(alpha_a))/(sqrt(3)*%pi*2);//in volts\n",
+"E_bo=V_ao-(I_ao*R_a);//in volts\n",
+"N_o=E_bo/K;\n",
+"disp(int(N_o),'No-Load Speed (in rpm)=');\n",
+"E_b=N*K;//in volts\n",
+"V_a=E_b+(I_a*R_a);//in volts\n",
+"alpha_ao=acosd(((V_a*%pi*2)/(3*V*sqrt(2)))-1);\n",
+"disp(alpha_ao,'Firing Angle (in degrees)=')"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.12: EX3_12.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:3.12\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"alpha=0.4;//duty cycle\n",
+"V_dc=200;//in volts\n",
+"R=10;//in ohms\n",
+"V_a=alpha*V_dc;\n",
+"disp(V_a,'(a) Average Load Voltage (in volts)=');\n",
+"I=V_a/R;\n",
+"disp(I,'(b) Average thyristor current (in amperes)=');\n",
+"I_d=0;\n",
+"disp(I_d,'(c) Diode Current (in amperes)=');\n",
+"R_eff=R/alpha;\n",
+"disp(R_eff,'(d) Effective input resistance (in ohms)=')"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.13: Find_the_value_of_average_load_current_and_firing_angle.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:3.13\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"V_dc=220;//in volts\n",
+"V_a=250;//average load voltage (in volts)\n",
+"R=10;//in ohms\n",
+"alpha=1-(V_dc/V_a);\n",
+"I=V_a/R;\n",
+"disp(I,'Average Load Current (in amperes)=')\n",
+"disp(alpha,'Firing Angle (in degrees)=')"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.14: Find_the_value_of_frequency_of_switching_pulse.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:3.14\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"V_dc=125;//in volts\n",
+"V_a=200;//average output voltage (in volts)\n",
+"T_on=1*10^-3;//in seconds\n",
+"alpha=V_a/(V_a+V_dc);//duty cycle\n",
+"f=alpha/T_on;\n",
+"disp(f,'Frequency Of Switching pulse (in hertz)=')"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.15: Find_the_value_of_frequency.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:3.15\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"alpha=0.25;//duty cycle\n",
+"V=400;//in volts\n",
+"L=0.5;//in henery\n",
+"I=10;//ripple current (in amperes)\n",
+"V_a=alpha*V;//in volts\n",
+"T_on=L*I/(V-V_a);//in seconds\n",
+"T=T_on/alpha;//in seconds\n",
+"f=1/T;\n",
+"disp(f,'Frequency (in hertzs)=')"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.16: Find_the_range_of_speed_control_and_duty_cycle.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:3.16\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"V_a=120;//in volts\n",
+"I_a=20;//in amperes\n",
+"R_a=0.5;//in ohms\n",
+"K=0.05;//Motor constant (in volts/rpm)\n",
+"E_b=V_a-(I_a*R_a);//in volts\n",
+"N=E_b/K;//in rpm\n",
+"disp('Range of Speed Control is :');\n",
+"disp('Lowest Speed (in rpm) = 0');\n",
+"disp(N,'Highest Speed (in rpm)=');\n",
+"E_bo=0;//in volts\n",
+"V_a1=E_bo+(I_a*R_a);//in volts\n",
+"alpha=V_a1/V_a;\n",
+"disp('Range of duty cycle is :');\n",
+"disp(alpha,'lowest value of duty cycle=');\n",
+"disp('Highest value of duty cycle= 1')"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.17: Find_the_value_of_duty_cycle_of_the_chopper.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:3.17\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"V=200;//in volts\n",
+"I_a=100;//in amperes\n",
+"R_a=0.02;//in ohms\n",
+"N1=940;//in rpm\n",
+"N2=500;//in rpm\n",
+"E_b1=V-(I_a*R_a);//in volts\n",
+"E_b2=E_b1*N2/N1;//in volts\n",
+"V_a=E_b2+(I_a*R_a);//in volts\n",
+"alpha=V_a/V;\n",
+"disp(alpha,'Duty Cycle Of The Chopper=')"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.18: Find_the_value_of_power_input_and_speed_and_torque_and_maximum_and_minimum_speed.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:3.18\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"alpha=0.6;//duty cycle\n",
+"alpha1=0.1;//duty cycle\n",
+"alpha2=0.9;//duty cycle\n",
+"V=400;//in volts\n",
+"R_a=0.1;//in ohms\n",
+"K=4;//Motor Constant (in Volts/radians)\n",
+"I_a=150;//in Amperes\n",
+"P_in=alpha*V*I_a/1000;\n",
+"disp(P_in,'(a) Power input (in Kilo-Watts)=');\n",
+"V_a=alpha*V;//in volts\n",
+"E_b=V_a-(I_a*R_a);//in volts\n",
+"N=60*E_b/(2*%pi*K);\n",
+"disp(int(N),'(b) Motor Speed (in rpm)=');\n",
+"T=E_b*I_a*60/(2*%pi*N);\n",
+"disp(T,'(c) Torque developed (in Newton-meter)=');\n",
+"E_b1=(alpha1*V)-(I_a*R_a);//in volts\n",
+"N1=60*E_b1/(2*%pi*K);\n",
+"disp(ceil(N1),'(d) Minimum Speed (in rpm)=')\n",
+"E_b2=(alpha2*V)-(I_a*R_a);//in volts\n",
+"N2=60*E_b2/(2*%pi*K);\n",
+"disp(ceil(N2),'    Maximum Speed (in rpm)=')"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.19: Find_the_value_of_Average_voltage_and_power_dissipated_and_speed.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:3.19\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"alpha=0.4;//duty cycle\n",
+"R_b=7.5;//in ohms\n",
+"R_a=0.1;//in ohms\n",
+"I_f=1.5;//in amperes\n",
+"K=1.6;//Voltage Constant (in V/A-rad/sec)\n",
+"I_a=150;//in amperes\n",
+"V_b=(1-alpha)*R_b*I_a;\n",
+"disp(V_b,'(a) Average Voltage (in volts)=');\n",
+"P_b=I_a^2*R_b*(1-alpha);\n",
+"disp(P_b/1000,'(b) Power Dissipated (in kilo-watts)=');\n",
+"E_g=V_b+(I_a*R_a);//in volts\n",
+"N=60*E_g/(K*I_f*2*%pi);\n",
+"disp(int(N),'(c) Speed (in rpm)=')"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.1: EX3_1.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:3.1\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"V=120;//in Volts\n",
+"V_dc=40.5;//in volts\n",
+"V_rms=76.1;//in volts\n",
+"R=10;//in ohms\n",
+"I_dc=V_dc/R;//in Amperes\n",
+"I_rms=V_rms/R;//in Amperes\n",
+"P_dc=V_dc*I_dc;//in watts\n",
+"P_ac=V_rms*I_rms;//in watts\n",
+"Eff=P_dc/P_ac;//in per unit\n",
+"disp(Eff,'(a) Efficiency (in Per Unit=)');\n",
+"K_f=V_rms/V_dc;//in per unit\n",
+"disp(K_f,'(b) Form Factor (in Per Unit=)');\n",
+"Y=sqrt(K_f^2-1);\n",
+"disp(Y,'(c) Ripple Factor (in Per Unit=)');\n",
+"T_f=P_dc/(V*I_rms);\n",
+"disp(T_f,'(d) Transformer Utilisation Factor=');\n",
+"P_iv=sqrt(2)*V;\n",
+"disp(P_iv,'(e) Peak Inverse Voltage (in volts)=')"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.20: Find_the_value_of_firing_angle_and_power_supplied.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:3.20\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"E_g=-163.53;//in volts\n",
+"I_a=40;//in amperes\n",
+"R_a=0.2;//in ohms\n",
+"V=220;//in volts\n",
+"V_a=E_g+(I_a*R_a);//in volts\n",
+"alpha_a=acosd(V_a*%pi/(2*V*sqrt(2)));\n",
+"disp(alpha_a,'Firing Angle (in degrees)=');\n",
+"P=V_a*I_a*(-1);\n",
+"disp(P/1000,'Power Supplied (in Kilo-Watts)=')"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.21: Find_the_value_of_pulse_width.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:3.21\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"E_b=100;//in volts\n",
+"I_a=25;//in amperes\n",
+"R=0.2;//(R_a+R_se) in ohms\n",
+"V=220;//in volts\n",
+"f=200;//in hertz\n",
+"V_a=E_b+(I_a*R);//in volts\n",
+"T_on=V_a/(V*f);\n",
+"disp(T_on*1000,' Pulse Width (in mili-seconds)')"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.22: Find_the_value_of_motor_torque.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:3.22\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"N=1000;//in rpm\n",
+"V=240;//in volts\n",
+"w=2*%pi*N/60;//in rad/sec\n",
+"alpha=30;//in degrees\n",
+"R=0.25;//in ohms\n",
+"K=0.025;//in Nm/A^2\n",
+"disp('When controlled through semiconverter');\n",
+"V_a1=sqrt(2)*V*(1+cosd(alpha))/%pi;//in volts\n",
+"I_a1=V_a1/(R+(K*w));\n",
+"disp(I_a1,'Armature Current (in Amperes)=');\n",
+"T_1=K*I_a1^2;\n",
+"disp(T_1,'Motor Torque (in N-m)=');\n",
+"disp('When controlled through full converter');\n",
+"V_a2=2*sqrt(2)*V*cosd(alpha)/%pi;//in volts\n",
+"I_a2=V_a2/(R+(K*w));\n",
+"disp(I_a2,'Armature Current (in Amperes)=');\n",
+"T_2=K*I_a2^2;\n",
+"disp(T_2,'Motor Torque (in N-m)=');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.23: Find_average_motor_current_and_speed.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:3.23\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"V=230;//in volts\n",
+"V_dc=sqrt(2)*V*2/%pi;//in volts\n",
+"T_L=30;//in N-m\n",
+"K_t=0.3;//torque constant (in N-m/A^2)\n",
+"I_a=sqrt(T_L/K_t);\n",
+"disp(I_a,'Average Motor Current (in Amperes)=');\n",
+"w=(207-I_a)/(K_t*I_a);// in rad/sec\n",
+"N=w*60/(2*%pi);\n",
+"disp(N,'Speed (in rpm)=');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.24: Find_the_value_of_armature_current_and_firing_angle.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:3.24\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"I_a1=36;//in amperes\n",
+"N1=400;//in amperes\n",
+"N2=600;//in amperes\n",
+"alpha_1=100;//in degrees\n",
+"V=675;//in volts\n",
+"R=0.4;//in ohms\n",
+"V_a1=sqrt(2)*V*(1+cosd(alpha_1))/%pi;//in volts\n",
+"E_b1=V_a1-I_a1*R;//in volts\n",
+"I_a2=I_a1*N2/N1;//in amperes\n",
+"E_b2=E_b1*I_a2*N2/(I_a1*N1);//in volts\n",
+"V_a2=E_b2+21.6;///in volts\n",
+"alpha=acosd((V_a2*%pi/(sqrt(2)*V))-1);\n",
+"disp(I_a2,'Armature current (in Amperes)=');\n",
+"disp(alpha,'Firing angle (in degrees)=');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.2: Find_the_value_of_feild_current_and_firing_angle_and_input_power_factor.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:3.2\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"alpha_f=0;\n",
+"R_f=250;//in ohms\n",
+"K_f=0.8;//torque constant\n",
+"R_a=0.2;//in ohms\n",
+"V_const=0.8;//in volt/Amperes-radian/sec\n",
+"N=1000;// in rpm\n",
+"T_d=50;//In Newton-meter\n",
+"V_rms=220;//in volts\n",
+"V_f=int(V_rms*sqrt(2)*(1+cosd(alpha_f))/%pi);// Feild Circuit Voltage (in volts)\n",
+"I_f=V_f/R_f;//in Amperes\n",
+"disp(I_f,'(a) Feild Current (in Amperes)=');\n",
+"I_a=T_d/(K_f*I_f);//in amperes\n",
+"w=2*N*%pi/60;// in radian/sec\n",
+"E_b=V_const*w*I_f;//Back emf (in volts)\n",
+"V_a=E_b+(I_a*R_a);//armature voltage (in volts)\n",
+"alpha_a=acosd(((V_a*%pi/(V_rms*sqrt(2))))-1);\n",
+"disp(alpha_a,'(b) Firing angle of the converter (in degrees)=');\n",
+"P_o=int(V_a*I_a);//in watts\n",
+"I=52.66;//in amperes\n",
+"pf=P_o/(V_rms*I);\n",
+"disp(pf,'(c) Power factor of the converter=')"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.3: Find_the_value_of_speed_of_motor_and_motor_torque.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:3.3\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"alpha_a=45;//in degrees\n",
+"V=230;//in volts\n",
+"K=1.668;//K_a*Phy (in volt/radian/second)\n",
+"R_a=0.2;//in ohms\n",
+"I_a=30;//in amperes\n",
+"V_a=2*V*sqrt(2)*cosd(alpha_a)/%pi;//in volts\n",
+"E_b=V_a-(I_a*R_a);// in volts\n",
+"w=E_b/K;//in radian/seconds\n",
+"N=ceil(w*60/(2*%pi));\n",
+"disp(N,'(a) Speed Of Motor (in rpm)=')\n",
+"T=K*I_a;\n",
+"disp(T,'(b) Motor Torque (in Newton-meter)=')"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.4: Find_the_value_of_firing_angle.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:3.4\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"R_a=0.06;//in ohms\n",
+"N1=875;// in rpm\n",
+"N2=750;//in rpm\n",
+"V_rms=220;//in volts\n",
+"V_dc=200;//in volts\n",
+"I_a=150;//in amperes\n",
+"E_b1=V_dc-(I_a*R_a);//Back emf (in volts)\n",
+"E_b2=E_b1*(N2/N1);// in volts\n",
+"V_a=E_b2+(I_a*R_a);//armature voltage (in volts)\n",
+"alpha_a=acosd((V_a*%pi/(2*V_rms*sqrt(2))));\n",
+"disp(alpha_a,'Firing angle (in degrees)=');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.5: Find_the_value_of_average_load_voltage_and_load_current_and_input_paower_factor.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:3.5\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"alpha=30;//in degrees\n",
+"V=230;//in volts\n",
+"R=2;//in ohms\n",
+"V_avg=2*V*sqrt(2)*cosd(alpha)/%pi;//in volts\n",
+"I_avg=V_avg/R;//in amperes\n",
+"disp(V_avg,'(a) Average Load Voltage (in Volts)=');\n",
+"disp(I_avg,'(b) Average Load Current (in Amperes)=')\n",
+"I_rms=I_avg;//in amperes (as ripple free)\n",
+"P=V_avg*I_avg;//in watts\n",
+"Q=2*V*sqrt(2)*I_avg*sind(alpha)/%pi;// in VAR\n",
+"pf=cosd(atand(Q/P));\n",
+"disp(pf,'(c) Input Power Factor (lagging)=')"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.6: Find_the_value_of_motor_armature_current_and_motor_speed.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:3.6\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"alpha=60;//in degrees\n",
+"V=250;//in volts\n",
+"T=140;//in Newton-Meter\n",
+"K_a=2.5;//motor voltage constant (in Volt/radian/sec)\n",
+"R_a=0.2;//in ohms\n",
+"V_a=2*V*sqrt(2)*cosd(alpha)/%pi;//in volts\n",
+"I_a=T/K_a;//in amperes\n",
+"disp(I_a,'(a) Motor Armature Current (in amperes)=');\n",
+"E_b=V_a-(I_a*R_a);//in volts\n",
+"w=E_b*I_a/T;\n",
+"disp(w,'(b) Motor Speed (in radian/sec)=')"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.7: Find_the_value_of_firing_angle.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:3.7\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"V_dc=220;//in volts\n",
+"V=230;//in volts\n",
+"I_a1=10;//in amperes\n",
+"N1=1500;//in rpm\n",
+"N2=500;//in rpm\n",
+"N3=-1000;//in rpm\n",
+"R_a=2;//in ohms\n",
+"E_b1=V_dc-(I_a1*R_a);//in volts\n",
+"E_b2=E_b1*(N2/N1);//in volts\n",
+"I_a2=I_a1/2;//in amperes\n",
+"V_a1=E_b2+(I_a2*R_a);//in volts\n",
+"alpha_a1=acosd((V_a1*%pi/(2*V*sqrt(2))));\n",
+"disp(alpha_a1,'(a) Firing angle (in degrees) at half the rated torque=');\n",
+"E_b3=E_b1*(N3/N1);//in volts\n",
+"I_a3=I_a1;//in amperes\n",
+"V_a2=E_b3+(I_a3*R_a);//in volts\n",
+"alpha_a2=acosd((V_a2*%pi/(2*V*sqrt(2))));\n",
+"disp(alpha_a2,'(b) Firing angle (in degrees) at rated motor torque=');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.8: Find_the_value_of_torque_developed_and_motor_speed.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:3.8\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"alpha_f=0;//in degrees\n",
+"alpha_a=30;//in degrees\n",
+"V=220;//in volts\n",
+"I_a=40;//in amperes\n",
+"R_a=0.2;//in amperes\n",
+"K_t=1.12;//motor voltage constant (in Volt/radian/sec)\n",
+"R_f=200;//in ohms\n",
+"V_f=2*V*sqrt(2)*cosd(alpha_f)/%pi;//in volts\n",
+"I_f=V_f/R_f;//in amperes\n",
+"V_a=2*V*sqrt(2)*cosd(alpha_a)/%pi;//in volts\n",
+"E_b=V_a-(I_a*R_a);//in volts\n",
+"T_d=K_t*I_a*I_f;\n",
+"disp(T_d,'(a) Torque developed (in N-m)=');\n",
+"N=E_b*60/(2*%pi*K_t*I_f);\n",
+"disp(ceil(N),'(b) Motor Speed (in rpm)=')"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.9: Find_the_value_of_firing_angle.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa:3.9\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"R_a=0.2;//in ohms\n",
+"alpha_f=0;//in degrees\n",
+"V=400;//in volts\n",
+"R_f=250;//in ohms\n",
+"K=1.3;//Volts/Ampere-radian/second\n",
+"N=1200;//in rpm\n",
+"I_a=60;//in amperes\n",
+"V_f=3*sqrt(3)*V*sqrt(2)/(sqrt(3)*%pi);//in volts\n",
+"I_f=V_f/R_f;//in amperes\n",
+"E_b=K*I_f*2*%pi*N/60;//in volts\n",
+"V_a=E_b+(I_a*R_a);//in volts\n",
+"alpha_a=acosd((V_a*%pi)/(3*V*sqrt(2)));\n",
+"disp(alpha_a,'Firing Angle (in degrees)=')"
+   ]
+   }
+],
+"metadata": {
+		  "kernelspec": {
+		   "display_name": "Scilab",
+		   "language": "scilab",
+		   "name": "scilab"
+		  },
+		  "language_info": {
+		   "file_extension": ".sce",
+		   "help_links": [
+			{
+			 "text": "MetaKernel Magics",
+			 "url": "https://github.com/calysto/metakernel/blob/master/metakernel/magics/README.md"
+			}
+		   ],
+		   "mimetype": "text/x-octave",
+		   "name": "scilab",
+		   "version": "0.7.1"
+		  }
+		 },
+		 "nbformat": 4,
+		 "nbformat_minor": 0
+}