17 files changed, 276 insertions, 0 deletions
diff --git a/1529/CH18/EX18.1/18_01.jpg b/1529/CH18/EX18.1/18_01.jpg
new file mode 100755
index 000000000..ca2f4ed69
--- /dev/null
+++ b/1529/CH18/EX18.1/18_01.jpg
diff --git a/1529/CH18/EX18.1/18_01.sce b/1529/CH18/EX18.1/18_01.sce
new file mode 100755
index 000000000..9459885f4
--- /dev/null
+++ b/1529/CH18/EX18.1/18_01.sce
@@ -0,0 +1,17 @@
+//Chapter 18, Problem 1
+clc;
+v=120;                  //dc supply
+c=15e-6;                //capacitance in farad
+r=47e3;                 //resistance in ohms
+taw=r*c;                //time constant
+t1=taw;
+vcta= v*(1-%e^(-1*t1/taw));
+vct = v/2;
+t = 0:0.1:10
+vc = v*(1-%e^(-1*t/taw));
+plot(t,vc)
+xtitle("capacitor voltage/time characteristic", "t", "Vc")
+t = -1*taw*log(1 - vct/v);
+
+printf("\n (a)The capacitor voltage at a time equal to one time constant = %.2f V",vcta)
+printf("\n (b)The time for the capacitor voltage to reach one half of its steady state value = %.1f sec",t)
diff --git a/1529/CH18/EX18.10/18_10.sce b/1529/CH18/EX18.10/18_10.sce
new file mode 100755
index 000000000..581951526
--- /dev/null
+++ b/1529/CH18/EX18.10/18_10.sce
@@ -0,0 +1,23 @@
+//Chapter 18, Problem 10
+clc;
+
+//initializing the variables:
+L = 3;                  //inductance in henry
+R = 15;                 //resistance in ohms
+V = 120;                //supply voltage
+t1 = 0.1;               // in secs
+t3 = 0.3;               // in secs
+
+//calculation:
+taw= L/R
+I = V/R
+i2 = 0.85*I
+VL = V*%e^(-1*t1/taw)
+t2 = -1*taw*log(1 - (i2/I))
+i3 = I*(1 - %e^(-1*t3/taw))
+
+printf("(a)Steady state value of current = %.0f A\n\n",I)
+printf("(b)Time constant of the circuit = %.3f sec\n\n",taw)
+printf("(c)Value of the induced e.m.f. after 0.1 s = %.2f V\n\n",VL)
+printf("(d)Time for the current to rise to 0.85 times of its final values = %.3f sec\n\n",t2)
+printf("(e)Value of the current after 0.3 s = %.3f A\n\n",i3)
diff --git a/1529/CH18/EX18.11/18_11.jpg b/1529/CH18/EX18.11/18_11.jpg
new file mode 100755
index 000000000..d2ebfc303
--- /dev/null
+++ b/1529/CH18/EX18.11/18_11.jpg
diff --git a/1529/CH18/EX18.11/18_11.sce b/1529/CH18/EX18.11/18_11.sce
new file mode 100755
index 000000000..664002835
--- /dev/null
+++ b/1529/CH18/EX18.11/18_11.sce
@@ -0,0 +1,24 @@
+//Chapter 18, Problem 11
+clc;
+
+//initializing the variables:
+R = 15;                 //resistance in ohms
+V = 110;                //supply voltage
+taw = 2;                //time constant
+t1 = 3;                 // in secs
+i2 =5;                  // in amperes
+
+//calculation:
+L = taw*R
+t = 0:0.1:10
+I = V/R
+i = I*(%e^(-1*t/taw))
+plot2d(t,i)
+xtitle("current/time characteristic", "t", "i")
+i1 = I*(%e^(-1*t1/taw))
+t2 = -1*taw*log((i2/I))
+
+
+printf("\n Inductance is %.0f H\n\n",L)
+printf("\n (a)The current flowing in the winding 3 s after being shorted-out = %.2f A\n\n",i1)
+printf("\n (b)The time for the current to decay to 5 A = %.3f sec\n\n",t2)
diff --git a/1529/CH18/EX18.12/18_12.sce b/1529/CH18/EX18.12/18_12.sce
new file mode 100755
index 000000000..5bb5e9e22
--- /dev/null
+++ b/1529/CH18/EX18.12/18_12.sce
@@ -0,0 +1,20 @@
+//Chapter 18, Problem 12
+clc;
+//initializing the variables:
+L = 6;              //inductance in henry
+r = 10;             //resistance in ohms
+V = 120;            //supply voltage
+taw = 0.3;          //time constant
+t1 = 1;             // in secs
+
+//calculation:
+R = (L/taw) - r
+Rt = R + r
+I = V/Rt
+i2 = 0.1*I
+i1 = I*(%e^(-1*t1/taw))
+t2 = -1*taw*log((i2/I))
+
+printf("\n (a)Resistance of the coil = %.0f ohm\n\n",R)
+printf("\n (b)Current flowing in the circuit one second after the shorting link has been placed = %.3f A\n\n",i1)
+printf("\n (c)The time for the current to decay to 0.1 times of initial value = %.3f sec\n\n",t2)
diff --git a/1529/CH18/EX18.13/18_13.sce b/1529/CH18/EX18.13/18_13.sce
new file mode 100755
index 000000000..d352bece6
--- /dev/null
+++ b/1529/CH18/EX18.13/18_13.sce
@@ -0,0 +1,21 @@
+//Chapter 18, Problem 13
+clc;
+//initializing the variables:
+L = 0.2;                    //inductance in henry
+R = 1000;                   //resistance in ohms
+V = 24;                     //supply voltage
+
+//calculation:
+taw = L/R
+t1 = 1*taw // in secs
+t2 = 2*taw // in secs
+t3 = 3*taw // in secs
+I = V/R
+i1 = I*(1 - %e^(-1*t1/taw))
+VL = V*(%e^(-1*t2/taw))
+VR = V*(1 - %e^(-1*t3/taw))
+
+printf("\n Time constant of the circuit is %.4f sec, and  the steady-state value of the current is %.3f A",taw, I)
+printf("\n (a) Current flowing in the circuit at a time equal to one time constant = %.5f A\n\n",i1)
+printf("\n (b) Voltage drop across the inductor at a time equal to two time constants = %.3f V\n\n",VL)
+printf("\n (c)The voltage drop across the resistor after a time equal to three time constants = %.2f V\n\n",VR)
diff --git a/1529/CH18/EX18.2/18_02.JPG b/1529/CH18/EX18.2/18_02.JPG
new file mode 100755
index 000000000..136b4d003
--- /dev/null
+++ b/1529/CH18/EX18.2/18_02.JPG
diff --git a/1529/CH18/EX18.2/18_02.sce b/1529/CH18/EX18.2/18_02.sce
new file mode 100755
index 000000000..dc7c969bf
--- /dev/null
+++ b/1529/CH18/EX18.2/18_02.sce
@@ -0,0 +1,28 @@
+//Chapter 18, Problem 2
+clc;
+//initializing the variables:
+c = 4E-6;                       //capacitance in farad
+r = 220000;                     //resistance in ohm
+V = 24;                         //supply voltage
+t1 = 1.5; 
+
+//calculation:
+taw = r*c
+t = 0:0.1:10
+Vc = V*(1-%e^(-1*t/taw));
+plot2d(t,Vc)
+xtitle("capacitor voltage/time characteristic", "t", "Vc")
+xset('window',1)
+VR = V*(1-%e^(-1*t/taw));
+plot2d(t,VR)
+xtitle("resistor voltage/time characteristic", "t", "VR")
+xset('window',2)
+I = V/r
+i = I*%e^(-1*t/taw)
+plot2d(t,i)
+xtitle("current/time characteristic", "t", "i")
+Vct1 = V*%e^(-1*t1/taw)
+VRt1 = V*%e^(-1*t1/taw)
+it1 = I*%e^(-1*t1/taw)
+
+printf("\n The value of capacitor voltage is %.2f V,\n\n resistor voltage is %.2f V,\n\n current is %.1E A at one and a half seconds after discharge has started.",Vct1, VRt1,it1)
diff --git a/1529/CH18/EX18.3/18_03.sce b/1529/CH18/EX18.3/18_03.sce
new file mode 100755
index 000000000..cebb671a5
--- /dev/null
+++ b/1529/CH18/EX18.3/18_03.sce
@@ -0,0 +1,23 @@
+//Chapter 18, Problem 3
+clc;
+//initializing the variables:
+C = 20E-6;                      //capacitance in farads
+R = 50000;                      //resistance in ohms
+V = 20;                         //supply voltage
+t1 = 1;                         // in secs
+t2 = 2;                         // in secs
+VRt = 15;                       // in volts
+
+//calculation:
+taw = R*C
+I = V/R
+Vct1 = V*(1-%e^(-1*t2/taw))
+t3 = -1*taw*log(VRt/V)
+it1 = I*%e^(-1*t1/taw)
+
+
+printf("\n (a)Initial value of the current flowing = %.4f mA\n\n",I*10^3)
+printf("\n (b)Time constant of the circuit = %.0f sec\n\n",taw)
+printf("\n (c)The value of the current one second after connection = %.3f mA\n\n",(it1/1E-3))
+printf("\n (d)The value of the capacitor voltage two seconds after connection = %.2f V\n\n",Vct1)
+printf("\n (e)The time after connection when the resistor voltage is 15 V = %.3f sec\n\n",t3)
diff --git a/1529/CH18/EX18.4/18_04.sce b/1529/CH18/EX18.4/18_04.sce
new file mode 100755
index 000000000..424ddb9ce
--- /dev/null
+++ b/1529/CH18/EX18.4/18_04.sce
@@ -0,0 +1,10 @@
+//Chapter 18, Problem 4
+clc;
+t=12e-3;                                           //time constant
+v=10;                                             //supply voltage
+t1=7e-3;                                         //time period of capacitor
+C=0.5e-6;                                        //capacitance
+R=t/C;                                           //calculating resistance
+vc=v*(1-exp(-t1/t));                            //calculating capacitor voltage
+printf("(a) Resistor = %d K.ohm\n\n",R/1000);
+printf("(b) Capacitor voltage = %f V",vc);
diff --git a/1529/CH18/EX18.5/18_05.sce b/1529/CH18/EX18.5/18_05.sce
new file mode 100755
index 000000000..15a36ac32
--- /dev/null
+++ b/1529/CH18/EX18.5/18_05.sce
@@ -0,0 +1,28 @@
+//Chapter 18, Problem 5
+clc;
+//Initializing the variables
+C=10*10^-6;                 //capacitance in farad
+R=25*10^3;                  //resistance in ohm
+V=100;                      //voltage dc supply
+t1=0.5;                     //time in seconds
+t2=0.1;                     //time in seconds
+vc1=45;                     //capacitor voltage 
+Vm=V;
+
+//Calculation
+taw=C*R;                                //time constant
+Im=V/R;                                 //maximum current
+vc=Vm*(1-exp(-t1/taw));                 //voltage across the capacitor
+i=Im*exp(-taw/taw);                     //current flowing after one time constant
+vr=V*exp(-t2/taw);                      //voltage across the resistor
+t3=-(log(1-(vc1/Vm))/log(exp(1)))*taw;  //time in seconds
+vt=V/taw;                               //initial rate of voltage rise
+
+
+printf("\n(a) Time constant = %f sec\n",taw);
+printf("\n(b) Maximum current = %f mA\n",Im*10^3);
+printf("\n(c) Voltage across the capacitor after 0.5 s = %f V\n",vc);
+printf("\n(d) Current flowing after one time constant = %f mA\n",i*10^3);
+printf("\n(e) Voltage across the resistor after 0.1 s = %f V\n",vr);
+printf("\n(f) Time for the capacitor voltage to reach 45V = %f s\n",t3);
+printf("\n(g) Initial rate of voltage rise = %f V\n",vt);
diff --git a/1529/CH18/EX18.6/18_06.sce b/1529/CH18/EX18.6/18_06.sce
new file mode 100755
index 000000000..a2c486ec4
--- /dev/null
+++ b/1529/CH18/EX18.6/18_06.sce
@@ -0,0 +1,23 @@
+//Chapter 18, Problem 6
+clc;
+
+//initializing the variables:
+R = 50000;              //resistance in ohms
+V = 100;                //supply voltage
+Vc1 = 20;               // in volts
+tou = 0.8;              // in secs
+t1 = 0.5;               // in secs
+t2 = 1;                 // in secs
+
+//calculation:
+C = tou/R
+t = -1*tou*log(Vc1/V)
+I = V/R
+it1 = I*%e^(-1*t1/tou)
+Vc = V*%e^(-1*t2/tou)
+
+
+printf("\n (a)The value of the capacitor = %f uF\n\n",C*10^6)
+printf("\n (b)The time for the capacitor voltage to fall to 20 V = %.2f sec\n\n",t)
+printf("\n (c)The current flowing when the capacitor has been discharging for 0.5 s = %f mA\n\n",it1*10^3)
+printf("\n (d)The voltage drop across the resistor when the capacitor has been discharging for one second = %.1f V\n\n",Vc)
diff --git a/1529/CH18/EX18.7/18_07.sce b/1529/CH18/EX18.7/18_07.sce
new file mode 100755
index 000000000..a9f04da88
--- /dev/null
+++ b/1529/CH18/EX18.7/18_07.sce
@@ -0,0 +1,17 @@
+//Chapter 18, Problem 7
+clc;
+
+//initializing the variables:
+C = 0.1E-6;             //capacitance in farads
+R = 4000;               //resistance in ohms
+V = 200;                //supply voltage
+Vc1 = 2;                // in volts
+
+//calculation:
+taw = R*C
+I = V/R
+t = -1*taw*log(Vc1/V)
+
+printf("\n (a)Initial discharge current = %.2f A\n\n",I)
+printf("\n (b)Time constant tou = %.4f sec\n\n",taw)
+printf("\n (c)Minimum time required for the voltage across the capacitor to fall to less than 2 V = %.3f sec",t)
diff --git a/1529/CH18/EX18.8/18_08.jpg b/1529/CH18/EX18.8/18_08.jpg
new file mode 100755
index 000000000..3917caed7
--- /dev/null
+++ b/1529/CH18/EX18.8/18_08.jpg
diff --git a/1529/CH18/EX18.8/18_08.sce b/1529/CH18/EX18.8/18_08.sce
new file mode 100755
index 000000000..bd6117562
--- /dev/null
+++ b/1529/CH18/EX18.8/18_08.sce
@@ -0,0 +1,22 @@
+//Chapter 18, Problem 8
+clc;
+//initializing the variables:
+L = 0.1;                //inductance in henry
+R = 20;                 //resistance in ohms
+V = 60;                 //supply voltage
+i2 = 1.5;               // in amperes
+
+//calculation:
+taw = L/R
+t1 = 2*taw
+t = 0:0.0001:0.025
+I = V/R
+i = I*(1 - %e^(-1*t/taw))
+plot2d(t,i)
+xtitle("current/time characteristic", "t", "i")
+i1 = I*(1 - %e^(-1*t1/taw))
+t2 = -1*taw*log(1 - i2/I)
+
+
+printf("\n (a)The value of current flowing at a time equal to two time constants = %.3f A\n\n",i1)
+printf("\n (b)The time for the current to grow to 1.5 A = %.7f sec\n\n",t2)
diff --git a/1529/CH18/EX18.9/18_09.sce b/1529/CH18/EX18.9/18_09.sce
new file mode 100755
index 000000000..6ba7e6e0e
--- /dev/null
+++ b/1529/CH18/EX18.9/18_09.sce
@@ -0,0 +1,20 @@
+//Chapter 18, Problem 9
+clc;
+//initializing the variables:
+L = 0.04;               //inductance in henry
+R = 10;                 //resistance in ohms
+V = 120;                //supply voltage
+
+
+//calculation:
+taw = L/R
+t1 = taw
+I = V/R
+i1 = I*(1 - %e^(-1*t1/taw))
+i2 = 0.01*I
+t2 = -1*taw*log(i2/I)
+
+printf("(a)The final value of current = %.0f A\n\n",I);
+printf("(b)Time constant of the circuit = %.3f sec\n\n",taw);
+printf("(c)Value of current after a time equal to the time constant = %.2f A\n\n",i1);
+printf("(d)The expected time for the current to rise to within 0.01 times of its final value = %.2f sec\n\n",t2);