initial commit / add all books

12 files changed, 243 insertions, 0 deletions

diff --git a/3760/CH8/EX8.1/ExA_1.sce b/3760/CH8/EX8.1/ExA_1.sce
new file mode 100644
index 000000000..a478018e7
--- /dev/null
+++ b/3760/CH8/EX8.1/ExA_1.sce
@@ -0,0 +1,14 @@
+clc;

+// answer is given wrong in the book

+d=0.2; // mean diameter of mild steel ring

+ac=50*10^-4; // cross sectional area of core

+uo=4*%pi*10^-7; // free space permeability

+ur=800; // relative permeability

+f=1*10^-3; // required flux

+N=200; // Number of turns

+l=%pi*d // length of core

+R=l/(uo*ur*ac); // reluctance of ring

+printf('reluctance offered by ring is %f AT/Wb\n',R);

+mmf=f*R; // mmf produced in ring

+i=mmf/N;

+printf('current required to produce the desired flux is %f A',i);

diff --git a/3760/CH8/EX8.10/ExA_10.sce b/3760/CH8/EX8.10/ExA_10.sce
new file mode 100644
index 000000000..6899006fd
--- /dev/null
+++ b/3760/CH8/EX8.10/ExA_10.sce
@@ -0,0 +1,7 @@
+clc;

+l=0.5; // length of conductor lying along Y-axis

+B=1.2; // Flux density along the X-axis

+v=2; // velocity of conductor

+//e=Blv; for maximum induced emf all the three quantities should be perpendicular to each other

+e=B*l*v; 

+printf('Maximum induced EMF in conductor is %f V',e);

diff --git a/3760/CH8/EX8.12/ExA_12.sce b/3760/CH8/EX8.12/ExA_12.sce
new file mode 100644
index 000000000..2c6304242
--- /dev/null
+++ b/3760/CH8/EX8.12/ExA_12.sce
@@ -0,0 +1,22 @@
+clc;

+disp('case a');

+// as per the data taken from Ex 1_3

+rlg=24.948*10^5; // air gap reluctance for example 1_3(a)

+rlc=12.474*10^5; // iron core reluctance for example 1_3(a)

+rl=rlg+rlc; // net reluctance

+N=500; // Number of turns 

+L=(N^2/rl)*1000;

+printf('Inductance for case a is %f mH\n',L);

+disp('case b');

+// as per the data taken from Ex 1_3 part(c)

+B=1.254; // calculated flux density

+H=3200; // magnetic field intensity obtained from magnetisation curve corresponding to the flux density calculated

+uo=4*%pi*10^-7; // free space permeability

+ur=B/(H*uo); // relative permeability of iron core

+d=2.85*10^-2; // diameter of cross section

+A=(%pi*d^2)/4; // area of core

+l=0.5; // core length

+rlc=l/(ur*uo*A); // reluctance of iron core for part C

+rt=rlg+rlc; // net reluctance

+L=(N^2/rt)*1000;  

+printf('Inductance for case b is %f mH\n',L);

diff --git a/3760/CH8/EX8.13/ExA_13.sce b/3760/CH8/EX8.13/ExA_13.sce
new file mode 100644
index 000000000..0c47fce1a
--- /dev/null
+++ b/3760/CH8/EX8.13/ExA_13.sce
@@ -0,0 +1,14 @@
+clc;

+// data taken from Ex A.7, fig A.16

+N1=200; // number of turns in coil 1

+f1=53.97*10^-3; // flux in outer limb containing coil 1

+m1=5000; // mmf for coil 1

+I1=m1/N1; // current in coil 1

+N2=100; // number of turns in coil 2

+f2=43.97*10^-3; // flux in outer limb containing coil 2

+m2=1102; // mmf for coil 2

+I2=m2/N2; // current in coil 2

+L1=(N1*f1)/I1; 

+printf('Inductance for coil 1 is %f H\n',L1);

+L2=(N2*f2)/I2; 

+printf('Inductance for coil 2 is %f H\n',L2);

diff --git a/3760/CH8/EX8.2/ExA_2.sce b/3760/CH8/EX8.2/ExA_2.sce
new file mode 100644
index 000000000..7055ff815
--- /dev/null
+++ b/3760/CH8/EX8.2/ExA_2.sce
@@ -0,0 +1,13 @@
+clc;

+ur=10000; // relative permeability of iron

+lc=0.5; // core length

+lg=4*10^-3; // air gap length

+N=600; // number of turns

+B=1.2; // desired flux density

+uo=4*%pi*10^-7; // free space permeability

+Ac=25*10^-4; // core area

+mfc=(B*lc)/(uo*ur); // mmf for core

+mfg=(B*lg)/uo; // mmf for air gap

+mft=mfc+mfg; // net mmf

+i=mft/N; 

+printf('exciting current required to establish the desired flux is %f A',i);

diff --git a/3760/CH8/EX8.3/ExA_3.sce b/3760/CH8/EX8.3/ExA_3.sce
new file mode 100644
index 000000000..7c06456b2
--- /dev/null
+++ b/3760/CH8/EX8.3/ExA_3.sce
@@ -0,0 +1,35 @@
+clc;

+lc=0.5; // core length in metre

+dc=2.85*10^-2; // diameter of cross section of core

+lg=2*10^-3; // length of air gap

+N=500; // Number oof turns of coil

+f=0.8*10^-3; // air gap flux

+uo=4*%pi*10^-7; // permeability of free space

+HATM=[1500 2210 2720 3500 4100];

+BT=[0.9 1.1 1.2 1.275 1.3];

+plot(HATM,BT);

+xlabel('magnetic field intensity');

+ylabel('flux density');

+disp('case a');

+ur=500; // relative permeability

+Ac=(%pi/4)*dc^2; // Area of core

+Rlg=lg/(uo*Ac); // reluctance of air gap

+Rlc=lc/(uo*ur*Ac); // reluctance of iron core

+Rt=Rlg+Rlc; // Total reluctance

+I=(f*Rt)/N; // Exciting current

+printf('Exciting current in coil is %f A\n',I);

+disp('case b');

+Ag=(%pi/4)*(dc+2*lg)^2; // air gap area 

+Rlg=lg/(uo*Ag); // reluctance of air gap

+I=(f*(Rlc+Rlg))/N; // Exciting current

+printf('Exciting current after accounting for flux fringing is %f A\n',I);

+disp('case c');

+Bg=f/Ac; // Air gap flux density

+Atg=(Bg*lg)/uo; // air gap mmf

+// from the plot we can get the values of core flux density and magnetic field intensity

+Bc=1.245; // core flux density in Tesla

+H=3200; // magnetic field intensity in Ats/m

+Atc=H*lc; // core mmf

+mt=Atg+Atc; // total mmf

+I=mt/N; // Exciting current

+printf('Exciting current for third case is %f A',I);

diff --git a/3760/CH8/EX8.4/ExA_4.sce b/3760/CH8/EX8.4/ExA_4.sce
new file mode 100644
index 000000000..3b10615de
--- /dev/null
+++ b/3760/CH8/EX8.4/ExA_4.sce
@@ -0,0 +1,24 @@
+clc;

+N=1000; // Number of turns

+f=1*10^-3; // flux in central limb

+Ac=8*10^-4; // Area of central limb

+Ao=4*10^-4; // Area of outer limb

+lg=2*10^-3; // length of air gap

+lc=0.15; // length of central limb in metre 

+lo=0.25; // length of outer limb in metre 

+uo=4*%pi*10^-7; // permeability of free space

+disp('case a');

+// for ur=infinity, reluctance offered by cast steel is zero

+Rl1=lg/(uo*Ao); // reluctance offered by outer limb

+Rl2=lg/(uo*Ac); // reluctance offered by central limb

+// Assuming magnetic circuit as a close circuit, applying KVl in one of loop gives 

+I=(f*(Rl2+(Rl1/2)))/N;

+printf('Coil current for first case is %f A\n',I);

+disp('case b');

+ur=6000; // relative permability

+Rlc1=(lc+lo)/(uo*ur*Ao); // reluctance of outer steel core (including the top)

+Rlc2=(lc)/(uo*ur*Ac); // reluctance offered by central steel core

+r=(Rlc1+Rl1)/2; // resultant of outer reluctance

+// By kVL we get 

+I=(f*(Rlc2+Rl2+r))/N; 

+printf('Coil current for second case is %f A\n',I);

diff --git a/3760/CH8/EX8.5/ExA_5.sce b/3760/CH8/EX8.5/ExA_5.sce
new file mode 100644
index 000000000..4db15d1ed
--- /dev/null
+++ b/3760/CH8/EX8.5/ExA_5.sce
@@ -0,0 +1,22 @@
+clc;

+N=500; // number of turns in central limb

+ac=600*10^-6; // cross sectional area of central limb

+ao=375*10^-6; // cross sectional area of outer limb

+f=0.9*10^-3; // required flux in Weber

+lg=0.8*10^-3; // length of air gap

+lc=180*10^-3; // length of central limb

+lo=400*10^-3; // length of outer limb

+uo=4*%pi*10^-7; // free space permeability

+Bg=f/ac; // air gap flux density

+Hg=Bg/uo; // magnetic field intensity in air gap

+mg=Hg*lg; // mmf required for air gap

+// from fig A.7,for B=1.5T, H for cast steel is 3000Ats/m

+H=3000; // magnetic field intensity for cast steel

+mc=H*lc; // mmf in central limb

+Bo=f/(2*ao); // flux density in each outer limb

+// for B=1.2, H=1400

+H=1400; // magnetic field intensity for cast steel for given flux density

+mo=H*lo; // mmf for outer limb

+// By KVL 

+I=(mg+mo+mc)/N;

+printf('The exciting current required to establish the desired flux is %f A',I);

diff --git a/3760/CH8/EX8.6/ExA_6.sce b/3760/CH8/EX8.6/ExA_6.sce
new file mode 100644
index 000000000..14fb9ba3e
--- /dev/null
+++ b/3760/CH8/EX8.6/ExA_6.sce
@@ -0,0 +1,28 @@
+clc;

+N=400; // number of turns in coil

+ac=20*10^-4; // area of cemntral limb

+ao=15*10^-4; // area of outer iimb

+lg=1*10^-3; // length of air gap

+lc=40*10^-2; // length of central limb

+lo=60*10^-2; // length of each outer limb

+f=0.9*10^-3; // required flux

+uo=4*%pi*10^-7; // free space permeability

+Bg=f/ao; // air gap flux density

+mg=(Bg*lg)/uo; // mmf or air gap

+// for B=0.6,H=575 AT/m from fig A.7

+H=575; // magnetic flux intensity for given flux density

+mo=H*lo; // mmf of outer limb which contain air gap

+mt=mo+mg; // combined mmf of air gap and outer limb

+// this mmf acts across the other outer limb

+haeb=mt/lo; // magnetic field intensity in outer limb which does not contain air gap

+// for H=1370.77, B=1.19 T from fig A.7

+Bo=1.19; // flux density for given magnetic field intensity

+faeb=Bo*ao; // flux in outer limb

+fnet=f+faeb; // net flux through central limb

+Bc=fnet/ac; // flux density in central limb

+// from fig A.7

+H=1900; //  magnetic field intensity for given flux density

+mc=H*lc; // mmf in central limb

+// by KVL in one of the loop

+I=(mc+mt)/N; 

+printf('Exciting current required to establish the given flux is %f A',I)  

diff --git a/3760/CH8/EX8.7/ExA_7.sce b/3760/CH8/EX8.7/ExA_7.sce
new file mode 100644
index 000000000..78976b45f
--- /dev/null
+++ b/3760/CH8/EX8.7/ExA_7.sce
@@ -0,0 +1,24 @@
+clc;

+a=30*10^-4; // cross sectional area of ferromagnetic core

+uo=4*%pi*10^-7; // free space permeability

+ur=4000; // relative permeability for core

+f=10*10^-3; // flux in central limb

+n1=200; // number of turns in coil 1

+m1=5000; // mmf for coil 1

+n2=100; // number of turns in coil 2

+lc=0.3; // length of central limb

+lo=0.6; // length of outer limb

+lg=1*10^-3; // length of air gap

+rc=lc/(uo*ur*a); // reluctance for central limb

+ro=lo/(uo*ur*a); // reluctance for outer limb

+rg=lg/(uo*a); // reluctance for air gap

+mc=f*(rc+rg); // mmf in central limb

+// by KML, flux in outer limb containing coil 1 is 

+f1=(m1-mc)/ro; 

+// By flux law at node a in fig A.17, flux in outer limb contaning coil 2 is

+f2=f1-f; 

+// by mmf law , mmf in coil 2 is

+m2=mc-f2*ro; 

+I2=m2/n2; // current in coil 2, upper polarity is assumed positive

+printf('Current in coil 2 is %f A',I2);

+disp('As the mmf of coil 2 is positive , assumed polarity is correct. Therefore terminal A is positive because current enters through it and terminal B is negative ');

diff --git a/3760/CH8/EX8.8/ExA_8.sce b/3760/CH8/EX8.8/ExA_8.sce
new file mode 100644
index 000000000..3820eeb03
--- /dev/null
+++ b/3760/CH8/EX8.8/ExA_8.sce
@@ -0,0 +1,19 @@
+clc;

+l=0.8; // length of conductor

+B=1.2; // flux density of uniform magnetic field

+v=30; // speed of conductor

+disp('case a');

+// conductor motion is normal to field flux

+theta=90; // angle between direction of motion and field flux

+e=B*l*v*sin(theta*(%pi/180)); 

+printf('EMF induced is %f V\n',e);

+disp('case b');

+// conductor motion is at an angle of 30 degrees from direction of field 

+theta=30; // angle between direction of motion and field flux

+e=B*l*v*sin(theta*(%pi/180)); 

+printf('EMF induced is %f V\n',e);

+disp('case c');

+// conductor motion is parllel to field flux

+theta=0; // angle between direction of motion and field flux

+e=B*l*v*sin(theta*(%pi/180)); 

+printf('EMF induced is %f V\n',e);

diff --git a/3760/CH8/EX8.9/ExA_9.sce b/3760/CH8/EX8.9/ExA_9.sce
new file mode 100644
index 000000000..74e3923a3
--- /dev/null
+++ b/3760/CH8/EX8.9/ExA_9.sce
@@ -0,0 +1,21 @@
+clc;

+// After deriving the expression

+a=0.1; // side of square coil

+N=100; // number of turns

+n=1000; // speed of rotation on rpm

+B=1; // flux density of a uniform magnetic field

+disp('case a'); 

+theta=90; // angle of coil with the field

+w=(2*%pi*n)/60; // angular speed of coil in rad/s

+e=N*B*a^2*w*cos(theta*(%pi/180));

+printf('Emf induced in coil is %f V\n',e); 

+disp('case b'); 

+theta=30; // angle of coil with the field

+w=(2*%pi*n)/60; // angular speed of coil in rad/s

+e=N*B*a^2*w*cos(theta*(%pi/180));

+printf('Emf induced in coil is %f V\n',e); 

+disp('case c'); 

+theta=0; // angle of coil with the field

+w=(2*%pi*n)/60; // angular speed of coil in rad/s

+e=N*B*a^2*w*cos(theta*(%pi/180));

+printf('Emf induced in coil is %f V\n',e);