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-rw-r--r--147/CH2/EX2.1/Example2_1.sce27
-rw-r--r--147/CH2/EX2.1/Result2_1.txt7
-rw-r--r--147/CH2/EX2.10/Example2_10.sce14
-rw-r--r--147/CH2/EX2.10/Result2_10.txt1
-rw-r--r--147/CH2/EX2.11/Example2_11.sce11
-rw-r--r--147/CH2/EX2.11/Result2_11.txt1
-rw-r--r--147/CH2/EX2.12/Example2_12.sce19
-rw-r--r--147/CH2/EX2.12/Result2_12.txt2
-rw-r--r--147/CH2/EX2.13/Example2_13.sce18
-rw-r--r--147/CH2/EX2.13/Result2_13.txt2
-rw-r--r--147/CH2/EX2.14/Example2_14.sce26
-rw-r--r--147/CH2/EX2.14/Result2_14.txt3
-rw-r--r--147/CH2/EX2.15/Example2_15.sce30
-rw-r--r--147/CH2/EX2.15/Result2_15.txt1
-rw-r--r--147/CH2/EX2.16/Example2_16.sce16
-rw-r--r--147/CH2/EX2.16/Result2_16.txt3
-rw-r--r--147/CH2/EX2.17/Example2_17.sce19
-rw-r--r--147/CH2/EX2.17/Result2_17.txt1
-rw-r--r--147/CH2/EX2.18/Example2_18.sce22
-rw-r--r--147/CH2/EX2.18/Result2_18.txt4
-rw-r--r--147/CH2/EX2.19/Example2_19.sce27
-rw-r--r--147/CH2/EX2.19/Result2_19.txt1
-rw-r--r--147/CH2/EX2.2/Example2_2.sce16
-rw-r--r--147/CH2/EX2.2/Result2_2.txt2
-rw-r--r--147/CH2/EX2.3/Example2_3.sce15
-rw-r--r--147/CH2/EX2.3/Result2_3.txt1
-rw-r--r--147/CH2/EX2.4/Example2_4.sce14
-rw-r--r--147/CH2/EX2.4/Result2_4.txt2
-rw-r--r--147/CH2/EX2.6/Example2_6.sce25
-rw-r--r--147/CH2/EX2.6/Result2_6.txt1
-rw-r--r--147/CH2/EX2.7/Example2_7.sce11
-rw-r--r--147/CH2/EX2.7/Result2_7.txt1
-rw-r--r--147/CH2/EX2.8/Example2_8.sce19
-rw-r--r--147/CH2/EX2.8/Result2_8.txt1
-rw-r--r--147/CH2/EX2.9/Example2_9.sce18
-rw-r--r--147/CH2/EX2.9/Result2_9.txt1
36 files changed, 382 insertions, 0 deletions
diff --git a/147/CH2/EX2.1/Example2_1.sce b/147/CH2/EX2.1/Example2_1.sce
new file mode 100644
index 000000000..c8cd05b65
--- /dev/null
+++ b/147/CH2/EX2.1/Example2_1.sce
@@ -0,0 +1,27 @@
+close();
+clear;
+clc;
+//Three resistances 'R1', 'R2', 'R3' connected in parrallel
+R1 = 2100; //ohm
+R2 = 2100; //ohm
+R3 = 2100; //ohm
+V = 210; //V
+Req = 1/((1/R1)+(1/R2)+(1/R3));
+
+//(a)
+//total current 'I'
+I = V/Req;
+mprintf("The total current, I = %0.1f A\n\n",I);
+
+//(b)
+//current through each resistor
+I1 = V/R1;
+I2 = V/R2;
+I3 = V/R3;
+mprintf("The current through %d ohm resistor is %0.1f A\nThe current through %d ohm resistor is %0.1f A\nThe current through %d ohm resistor is %0.1f A\n\n",R1,I1,R2,I2,R3,I3);
+
+//(c)
+//total power dissipated in resistors 'P'
+P = V*I;
+mprintf("Total power dissipated in resistors, P = %d W",round(P));
+
diff --git a/147/CH2/EX2.1/Result2_1.txt b/147/CH2/EX2.1/Result2_1.txt
new file mode 100644
index 000000000..4dc07842e
--- /dev/null
+++ b/147/CH2/EX2.1/Result2_1.txt
@@ -0,0 +1,7 @@
+(a) The total current, I = 0.3 A
+
+(b) The current through 2100 ohm resistor is 0.1 A
+ The current through 2100 ohm resistor is 0.1 A
+ The current through 2100 ohm resistor is 0.1 A
+
+(c) Total power dissipated in resistors, P = 63 W \ No newline at end of file
diff --git a/147/CH2/EX2.10/Example2_10.sce b/147/CH2/EX2.10/Example2_10.sce
new file mode 100644
index 000000000..d37d6959c
--- /dev/null
+++ b/147/CH2/EX2.10/Example2_10.sce
@@ -0,0 +1,14 @@
+//Resistance R, Voltage V
+close();
+clear;
+clc;
+V = 110;//V
+//From previous question
+Rao = 1.5;//ohm
+Rbo = 1;
+Rco = 3;
+Rcd = 3;
+Rth = Rao + Rbo*(Rco+Rcd)/(Rbo+Rco+Rcd);
+//For maximum power
+Rad = Rth;
+mprintf('Rad = %0.2f ohm',Rad); \ No newline at end of file
diff --git a/147/CH2/EX2.10/Result2_10.txt b/147/CH2/EX2.10/Result2_10.txt
new file mode 100644
index 000000000..81ac39a3e
--- /dev/null
+++ b/147/CH2/EX2.10/Result2_10.txt
@@ -0,0 +1 @@
+Rad = 2.36 ohm \ No newline at end of file
diff --git a/147/CH2/EX2.11/Example2_11.sce b/147/CH2/EX2.11/Example2_11.sce
new file mode 100644
index 000000000..2e7c8abcd
--- /dev/null
+++ b/147/CH2/EX2.11/Example2_11.sce
@@ -0,0 +1,11 @@
+close();
+clear;
+clc;
+//thevenin resistance 'Rth'
+Rad = 33/14; //ohm
+Rth = Rad;
+//after converting 10 A current source into voltage source in Fig 2.14(b)
+Vth = 6/7 * 110; //V
+//total power 'P'
+P = Vth^2/(Rth+Rad); //W
+mprintf("Total power supplied to network,P = %d W",round(P)); \ No newline at end of file
diff --git a/147/CH2/EX2.11/Result2_11.txt b/147/CH2/EX2.11/Result2_11.txt
new file mode 100644
index 000000000..55900beb3
--- /dev/null
+++ b/147/CH2/EX2.11/Result2_11.txt
@@ -0,0 +1 @@
+Total power supplied to network,P = 1886 W \ No newline at end of file
diff --git a/147/CH2/EX2.12/Example2_12.sce b/147/CH2/EX2.12/Example2_12.sce
new file mode 100644
index 000000000..9386c46c6
--- /dev/null
+++ b/147/CH2/EX2.12/Example2_12.sce
@@ -0,0 +1,19 @@
+//Resistance R, Current source , Voltage source V1
+close();
+clear;
+clc;
+R1 = 30;//ohm
+R2 = 20;//ohm
+R3 = 10;//ohm
+R4 = 5;//ohm
+I = 10;//A
+V = 100;//V
+//Convertng Current source to voltage source
+V1 = I*R4;
+//Solving mesh equations
+A = [R2+R3+R4 -R2; -R2 R1+R2];
+C = [V1;-V];
+B = inv(A)*C;
+I1 = B(1,1);
+I2 = B(2,1);
+mprintf('I1 = %0.2f A \nI2 = %0.2f A',I1,I2); \ No newline at end of file
diff --git a/147/CH2/EX2.12/Result2_12.txt b/147/CH2/EX2.12/Result2_12.txt
new file mode 100644
index 000000000..ac4331cb5
--- /dev/null
+++ b/147/CH2/EX2.12/Result2_12.txt
@@ -0,0 +1,2 @@
+I1 = 0.37 A
+I2 = -1.85 A \ No newline at end of file
diff --git a/147/CH2/EX2.13/Example2_13.sce b/147/CH2/EX2.13/Example2_13.sce
new file mode 100644
index 000000000..c5c253aba
--- /dev/null
+++ b/147/CH2/EX2.13/Example2_13.sce
@@ -0,0 +1,18 @@
+close();
+clear;
+clc;
+I1 = 10; //A
+I2 = 100; //A
+R1 = 5; //ohm
+R2 = 10; //ohm
+R3 = 20; //ohm
+R4 = 30; //ohm
+//applying KCL
+A = [(1/R1+1/R2) (-1/R2);(1/R2) (-1/R2-1/R4-1/R3)];
+C = [I1;-I2/R4];
+B = inv(A)*C;
+V1 = B(1,1);
+V2 = B(2,1);
+I1 = (V1-V2)/R2;
+I2 = (V2-I2)/R4;
+mprintf("I1 = %0.2f A\nI2 = %0.2f A",I1,I2); \ No newline at end of file
diff --git a/147/CH2/EX2.13/Result2_13.txt b/147/CH2/EX2.13/Result2_13.txt
new file mode 100644
index 000000000..cf603434b
--- /dev/null
+++ b/147/CH2/EX2.13/Result2_13.txt
@@ -0,0 +1,2 @@
+I1 = 0.37 A
+I2 = -1.85 A \ No newline at end of file
diff --git a/147/CH2/EX2.14/Example2_14.sce b/147/CH2/EX2.14/Example2_14.sce
new file mode 100644
index 000000000..fa565240b
--- /dev/null
+++ b/147/CH2/EX2.14/Example2_14.sce
@@ -0,0 +1,26 @@
+//Resistance R, Current source , Voltage source V1
+close();
+clear;
+clc;
+R1 = 30;//ohm
+R2 = 20;//ohm
+R3 = 10;//ohm
+R4 = 5;//ohm
+I = 10;//A
+V = 100;//V
+//From previous question
+I1 = 0.37;//A
+I2 = -1.85;//A
+//Current through R4 'I3'
+I3 = I - I1;
+V1 = I3*R4;
+V2 = V+I2*R1;
+//Power from Current source 'P1'
+P1 = I*V1;
+//Power from voltage source 'P2'
+P2 = V*(-I2);
+//Total Power 'P'
+P = P1+P2;
+//Power dissipated in resistances 'Pr'
+Pr = V1^2/R4+I1^2*R3 + V2^2/R2 + I2^2*R1;
+mprintf('Sum of power from the sources P = %0.2f W\nPower dissipated by resistances P = %0.2f W \nHence Sum of the powers from the two sources is the total power dissipated in all the resistances.',P,Pr); \ No newline at end of file
diff --git a/147/CH2/EX2.14/Result2_14.txt b/147/CH2/EX2.14/Result2_14.txt
new file mode 100644
index 000000000..1e21b917b
--- /dev/null
+++ b/147/CH2/EX2.14/Result2_14.txt
@@ -0,0 +1,3 @@
+Sum of power from the sources P = 666.50 W
+Power dissipated by resistances P = 666.74 W
+Hence Sum of the powers from the two sources is the total power dissipated in all the resistances. \ No newline at end of file
diff --git a/147/CH2/EX2.15/Example2_15.sce b/147/CH2/EX2.15/Example2_15.sce
new file mode 100644
index 000000000..9a5a8963d
--- /dev/null
+++ b/147/CH2/EX2.15/Example2_15.sce
@@ -0,0 +1,30 @@
+close();
+clear;
+clc;
+Vs = 100; //V
+Is = 10; //A
+R1 = 5; //ohm
+R2 = 10; //ohm
+R3 = 30; //ohm
+R4 = 5; //ohm
+V2 = 90; //V
+R = 20;
+//When all current sources are open circuited and voltage sources are short circuited
+R20 = (R1+R2)*R3/(R1+R2+R3);
+Rn = R20;
+//current contribution due to 100 V source
+In1 = Vs/R3;
+//current contribution due to 10 A source
+In2 = Is*(R1)/(R1+R2); //A
+//by supersition principle 'In'
+In = In1+In2; //A
+//resistance seen by voltage source, 'Re'
+Re1 = (R1+R2)*R3/(R1+R2+R3) + R4;
+I1 = V2/Re1;
+//by current division, ammeter reading 'Ia'
+Ia = R3*I1/(R1+R2+R3);
+Re2 = (R1+R2) + (R3*R4)/(R3+R4); //ohm
+I2 = V2/Re2; //A
+//current in 20 ohm resistor 'I20'
+I20 = In*(R2/(R2+R)); //A
+mprintf("Current in 20 ohm resistance, I20 = %0.2f A",I20); \ No newline at end of file
diff --git a/147/CH2/EX2.15/Result2_15.txt b/147/CH2/EX2.15/Result2_15.txt
new file mode 100644
index 000000000..6a7bf264c
--- /dev/null
+++ b/147/CH2/EX2.15/Result2_15.txt
@@ -0,0 +1 @@
+Current in 20 ohm resistance, I20 = 2.22 A \ No newline at end of file
diff --git a/147/CH2/EX2.16/Example2_16.sce b/147/CH2/EX2.16/Example2_16.sce
new file mode 100644
index 000000000..6735ece6e
--- /dev/null
+++ b/147/CH2/EX2.16/Example2_16.sce
@@ -0,0 +1,16 @@
+//Resistance R, Voltage V
+close();
+clear;
+clc;
+R1 = 10;//ohm
+R2 = 5;
+R3 = 30;
+R4 = 5;
+V = 90;//V
+Ra = R4 + (R1+R2)*(R3)/(R1+R2+R3);
+I1 = V/Ra;
+Ia = R3/(R1+R2+R3)*I1;
+Rb = R1+R2+(R3*R4)/(R3+R4);
+I2 = V/Rb;
+Ib = R3/(R3+R4)*I2;
+mprintf('Ammeter reading for network 1 = %0.0f A\nAmmeter reading for network 2 = %0.0f A \nThe equality of the ammeter readings constitutes a special case of the reciprocity theorem.',Ia,Ib); \ No newline at end of file
diff --git a/147/CH2/EX2.16/Result2_16.txt b/147/CH2/EX2.16/Result2_16.txt
new file mode 100644
index 000000000..22be25c42
--- /dev/null
+++ b/147/CH2/EX2.16/Result2_16.txt
@@ -0,0 +1,3 @@
+Ammeter reading for network 1 = 4 A
+Ammeter reading for network 2 = 4 A
+The equality of the ammeter readings constitutes a special case of the reciprocity theorem. \ No newline at end of file
diff --git a/147/CH2/EX2.17/Example2_17.sce b/147/CH2/EX2.17/Example2_17.sce
new file mode 100644
index 000000000..0ece8f06e
--- /dev/null
+++ b/147/CH2/EX2.17/Example2_17.sce
@@ -0,0 +1,19 @@
+close();
+clear;
+clc;
+V = 100; //V
+Rab = 3; //ohm
+Rac = 6; //ohm
+Rbc = 9; //ohm
+Rao = 9; //ohm
+Rbo = 6; //ohm
+Rco = 3; //ohm
+rac = (Rao*Rco + Rao*Rbo + Rbo*Rco)/Rbo;
+rbc = (Rao*Rco + Rao*Rbo + Rbo*Rco)/Rao;
+rab = (Rao*Rco + Rao*Rbo + Rbo*Rco)/Rco;
+Rab1 = (rac*Rac/(rac+Rac)) + (rbc*Rbc/(rbc+Rbc));
+Rab2 = Rab*rab/(Rab+rab);
+R = Rab1*Rab2/(Rab1+Rab2);
+//power supplied 'P'
+P = V^2/R; //W
+mprintf("Power supplied, P = %0.1f W",P); \ No newline at end of file
diff --git a/147/CH2/EX2.17/Result2_17.txt b/147/CH2/EX2.17/Result2_17.txt
new file mode 100644
index 000000000..cf5d63789
--- /dev/null
+++ b/147/CH2/EX2.17/Result2_17.txt
@@ -0,0 +1 @@
+Power supplied, P = 4705.9 W \ No newline at end of file
diff --git a/147/CH2/EX2.18/Example2_18.sce b/147/CH2/EX2.18/Example2_18.sce
new file mode 100644
index 000000000..6c818b99d
--- /dev/null
+++ b/147/CH2/EX2.18/Example2_18.sce
@@ -0,0 +1,22 @@
+//Resistance R, Voltage V, Load resistance Rl
+close();
+clear;
+clc;
+R1 = 11/8;
+R2 = 1;
+R3 = 3;
+R4 = 2;
+V = 11;//V
+Rl1 = 9;//ohm
+Rl2 = 99;
+Rth = R1*(R2*R4+R2*R3+R3*R4)/(R1*R2+R2*R3+R3*R4+R4*R1+R2*R4);
+//To find Vth
+Req = R4 + R2*(R1+R3)/(R1+R2+R3);
+I = V/Req;
+I1 = R2/(R1+R3)*I;
+I2 = I-I1;
+Vth = I1*R3+I*R4;
+//Load Current for Rl1 'Il1'
+Il1 = Vth/(Rl1+Rth);
+Il2 = Vth/(Rl2+Rth);
+mprintf('Rth = %0.0f ohm \nVth = %0.0f ohm\nFor 9 ohm, Load Current I = %0.0f A\nFor 99 ohm, Load Current I = %0.1f A',Rth,Vth,Il1,Il2);
diff --git a/147/CH2/EX2.18/Result2_18.txt b/147/CH2/EX2.18/Result2_18.txt
new file mode 100644
index 000000000..9138ab16a
--- /dev/null
+++ b/147/CH2/EX2.18/Result2_18.txt
@@ -0,0 +1,4 @@
+Rth = 1 ohm
+Vth = 10 ohm
+For 9 ohm, Load Current I = 1 A
+For 99 ohm, Load Current I = 0.1 A \ No newline at end of file
diff --git a/147/CH2/EX2.19/Example2_19.sce b/147/CH2/EX2.19/Example2_19.sce
new file mode 100644
index 000000000..605b00be8
--- /dev/null
+++ b/147/CH2/EX2.19/Example2_19.sce
@@ -0,0 +1,27 @@
+close();
+clear;
+clc;
+Rab = 6; //ohm
+Rbc = 6; //ohm
+Rac = 6; //ohm
+Rad = 10; //ohm
+RcB1 = 8; //ohm
+RcB2 = 4; //ohm
+RcB3 = 10; //ohm
+RAb = 4; //ohm
+RAd1 = 4; //ohm
+RAd2 = 4; //ohm
+RAd3 = 6; //ohm
+//after transformation of network abc into star network
+Rao = Rab*Rac/(Rab+Rbc+Rac); //ohm
+Rbo = Rab*Rbc/(Rab+Rbc+Rac); //ohm
+Rco = Rbc*Rac/(Rab+Rbc+Rac); //ohm
+RAd = RAd1+RAd2+RAd3;
+RcB = RcB1+RcB2+RcB3;
+RAo = Rbo+RAb;
+RoB = Rco+RcB;
+Rod = Rao+Rad;
+RoB = RoB*Rod/(RoB+Rod);
+RAB1 = RAo + RoB;
+RAB = RAB1*RAd/(RAB1+RAd);
+mprintf("Equivalent resistance across A and B is, RAB = %0.3f ohm",RAB); \ No newline at end of file
diff --git a/147/CH2/EX2.19/Result2_19.txt b/147/CH2/EX2.19/Result2_19.txt
new file mode 100644
index 000000000..be0f4d08b
--- /dev/null
+++ b/147/CH2/EX2.19/Result2_19.txt
@@ -0,0 +1 @@
+Equivalent resistance across A and B is, RAB = 7.000 ohm \ No newline at end of file
diff --git a/147/CH2/EX2.2/Example2_2.sce b/147/CH2/EX2.2/Example2_2.sce
new file mode 100644
index 000000000..528db7422
--- /dev/null
+++ b/147/CH2/EX2.2/Example2_2.sce
@@ -0,0 +1,16 @@
+//Resistances connected in parallel R, Source voltage V, Limiting voltage Vl
+close();
+clear;
+clc;
+R = 700;//ohm
+V = 210;//V
+Vl = 110;//V
+//Cureent through each 700 ohm resistor 'I1'
+I1 = Vl/R;
+//Total current drawn from source 'I'
+I = 3*I1;
+//Voltage across series resistor 'Vx'
+Vx = V - Vl;
+Rx = Vx/I;
+P = V*I;
+mprintf('Value of series resistor Rx = %0.1f ohm\nPower drawn from source P = %0.1f W',Rx,P); \ No newline at end of file
diff --git a/147/CH2/EX2.2/Result2_2.txt b/147/CH2/EX2.2/Result2_2.txt
new file mode 100644
index 000000000..fbf40fb1f
--- /dev/null
+++ b/147/CH2/EX2.2/Result2_2.txt
@@ -0,0 +1,2 @@
+Value of series resistor Rx = 212.1 ohm
+Power drawn from source P = 99.0 W \ No newline at end of file
diff --git a/147/CH2/EX2.3/Example2_3.sce b/147/CH2/EX2.3/Example2_3.sce
new file mode 100644
index 000000000..4dd812313
--- /dev/null
+++ b/147/CH2/EX2.3/Example2_3.sce
@@ -0,0 +1,15 @@
+close();
+clear;
+clc;
+R1 = 12; //ohm
+R2 = 4; //ohm
+R3 = 5; //ohm
+R4 = 5; //ohm
+R5 = 15; //ohm
+//voltage across R1 'V1'
+V1 = 132; //V
+I = V1/R1;
+R = R1 + R2 + (R4+R5)*R3/(R3+R4+R5);
+//source voltage 'V'
+V = I*R;
+mprintf("The voltage source, V = %d V",round(V)); \ No newline at end of file
diff --git a/147/CH2/EX2.3/Result2_3.txt b/147/CH2/EX2.3/Result2_3.txt
new file mode 100644
index 000000000..0590ee3d4
--- /dev/null
+++ b/147/CH2/EX2.3/Result2_3.txt
@@ -0,0 +1 @@
+The voltage source, V = 220 V \ No newline at end of file
diff --git a/147/CH2/EX2.4/Example2_4.sce b/147/CH2/EX2.4/Example2_4.sce
new file mode 100644
index 000000000..6db7c40e2
--- /dev/null
+++ b/147/CH2/EX2.4/Example2_4.sce
@@ -0,0 +1,14 @@
+//Resistance R, Voltage V, Current I
+close();
+clear;
+clc;
+R1 = 5;//ohm
+R2 = 15;
+R3 = 5;
+R4 = 4;
+R5 = 12;
+V5 = 132;//V
+I = V5/R5;
+I1 = (R1+R2)/(R1+R2+R3)*I;
+I2 = R3/(R1+R2+R3)*I;
+mprintf('I1 = %0.1f A\nI2 = %0.1f A',I1,I2); \ No newline at end of file
diff --git a/147/CH2/EX2.4/Result2_4.txt b/147/CH2/EX2.4/Result2_4.txt
new file mode 100644
index 000000000..faa397ac6
--- /dev/null
+++ b/147/CH2/EX2.4/Result2_4.txt
@@ -0,0 +1,2 @@
+I1 = 8.8 A
+I2 = 2.2 A \ No newline at end of file
diff --git a/147/CH2/EX2.6/Example2_6.sce b/147/CH2/EX2.6/Example2_6.sce
new file mode 100644
index 000000000..007f351d8
--- /dev/null
+++ b/147/CH2/EX2.6/Example2_6.sce
@@ -0,0 +1,25 @@
+//Resistance R, Voltage V
+close();
+clear;
+clc;
+R1 = 6;//ohm
+R2 = 1;
+R3 = 2;
+R4 = 3;
+R5 = 10;
+V1 = 10;//V
+V2 = 20;
+//Short circuiting V1
+//Equvalent resistance across V2 'Req'
+Req = R5+(R1*R2/(R1+R2)+R3+R4)/(R4*(R1*R2/(R1+R2)+R3));
+I_1 = -V2/Req;
+//Short circutng V2
+A = [-(R1+R2) R2 0;R2 -(R2+R3+R4) R4;0 R4 -(R3+R4)];
+C = [-V1;0;0];
+B = inv(A)*C;
+I1 = B(1,1);
+I2 = B(2,1);
+I3 = B(3,1);
+I_2 = I3;
+I = I_1+I_2;
+mprintf('I = %0.2f A',I); \ No newline at end of file
diff --git a/147/CH2/EX2.6/Result2_6.txt b/147/CH2/EX2.6/Result2_6.txt
new file mode 100644
index 000000000..f804f7ba6
--- /dev/null
+++ b/147/CH2/EX2.6/Result2_6.txt
@@ -0,0 +1 @@
+I = -1.66 A \ No newline at end of file
diff --git a/147/CH2/EX2.7/Example2_7.sce b/147/CH2/EX2.7/Example2_7.sce
new file mode 100644
index 000000000..5a6b93a34
--- /dev/null
+++ b/147/CH2/EX2.7/Example2_7.sce
@@ -0,0 +1,11 @@
+close();
+clear;
+clc;
+//matrix of coefficient of I1, I2 and I3 'A'
+A = [7 -1 0;-1 6 -3;0 -3 13];
+C = [10;0;-20]
+B = inv(A)*C;
+I1 = B(1,1);
+I2 = B(2,1);
+I3 = B(3,1);
+mprintf("By mesh analysis, I3 = %0.2f A",I3); \ No newline at end of file
diff --git a/147/CH2/EX2.7/Result2_7.txt b/147/CH2/EX2.7/Result2_7.txt
new file mode 100644
index 000000000..c34836873
--- /dev/null
+++ b/147/CH2/EX2.7/Result2_7.txt
@@ -0,0 +1 @@
+By mesh analysis, I3 = -1.68 A \ No newline at end of file
diff --git a/147/CH2/EX2.8/Example2_8.sce b/147/CH2/EX2.8/Example2_8.sce
new file mode 100644
index 000000000..60121924d
--- /dev/null
+++ b/147/CH2/EX2.8/Example2_8.sce
@@ -0,0 +1,19 @@
+//Resistance R, Voltage V
+close();
+clear;
+clc;
+R1 = 6;//ohm
+R2 = 1;
+R3 = 2;
+R4 = 3;
+R5 = 10;
+V1 = 10;//V
+V2 = 20;
+//Solving Nodal equations
+A = [1/R1+1/R2+1/R3 -1/R3;-1/R3 1/R3+1/R4+1/R5];
+C = [V1/R1;V2/R5];
+B = inv(A)*C;
+V3 = B(1,1);
+V4 = B(2,1);
+I = (V4-V2)/R5;
+mprintf('I = %0.2f A',I); \ No newline at end of file
diff --git a/147/CH2/EX2.8/Result2_8.txt b/147/CH2/EX2.8/Result2_8.txt
new file mode 100644
index 000000000..e3ae3e929
--- /dev/null
+++ b/147/CH2/EX2.8/Result2_8.txt
@@ -0,0 +1 @@
+I = -1.68 A \ No newline at end of file
diff --git a/147/CH2/EX2.9/Example2_9.sce b/147/CH2/EX2.9/Example2_9.sce
new file mode 100644
index 000000000..ac2414a15
--- /dev/null
+++ b/147/CH2/EX2.9/Example2_9.sce
@@ -0,0 +1,18 @@
+close();
+clear;
+clc;
+Rab = 3; //ohm
+Rbc = 6; //ohm
+Rac = 9; //ohm
+Rad = 4.5; //ohm
+Rcd = 3; //ohm
+//transforming abc network into star network
+Rbo = Rab*Rbc/(Rab+Rbc+Rac);
+Rao = Rab*Rac/(Rab+Rbc+Rac);
+Rco = Rbc*Rac/(Rab+Rbc+Rac);
+Rod1 = Rao+Rad;
+Rod2 = Rco+Rcd;
+Rod = Rod1*Rod2/(Rod1+Rod2);
+//equivalent resistance at terminals AB
+RAB = Rbo + Rod;
+mprintf("\nThe equivalent resistance at terminals AB = %d ohm",RAB); \ No newline at end of file
diff --git a/147/CH2/EX2.9/Result2_9.txt b/147/CH2/EX2.9/Result2_9.txt
new file mode 100644
index 000000000..f7a9c8d2f
--- /dev/null
+++ b/147/CH2/EX2.9/Result2_9.txt
@@ -0,0 +1 @@
+The equivalent resistance at terminals AB = 4 ohm \ No newline at end of file