4 files changed, 76 insertions, 0 deletions
diff --git a/3665/CH7/EX7.1/Ex7_1.sce b/3665/CH7/EX7.1/Ex7_1.sce
new file mode 100644
index 000000000..6e7087077
--- /dev/null
+++ b/3665/CH7/EX7.1/Ex7_1.sce
@@ -0,0 +1,18 @@
+clc//
+//
+//
+
+//Variable declaration
+rho_s=10.5*10^3;     //density(kg/m^3)
+NA=6.02*10^26;       //avagadro number(per k mol)
+MA=107.9;      //atomic mass
+sigma=6.8*10^7;     //conductance(ohm-1 m-1)
+e=1.6*10^-19;     //charge(coulomb)
+
+//Calculation
+n=rho_s*NA/MA;     //density of electrons
+mew=sigma/(n*e);    //mobility of electrons(m^2/Vs)
+
+//Result
+printf("\n density of electrons is %0.2f *10^28",n/10^28)
+printf("\n mobility of electrons is %0.3f *10^-2 m^2 V-1 s-1",mew*10^2)
diff --git a/3665/CH7/EX7.2/Ex7_2.sce b/3665/CH7/EX7.2/Ex7_2.sce
new file mode 100644
index 000000000..c4588d2b4
--- /dev/null
+++ b/3665/CH7/EX7.2/Ex7_2.sce
@@ -0,0 +1,20 @@
+clc//
+//
+//
+
+//Variable declaration
+d=8.92*10^3;     //density(kg/m^3)
+rho=1.73*10^-8;     //resistivity of copper(ohm m)
+NA=6.02*10^26;       //avagadro number(per k mol)
+Aw=63.5;      //atomic weight
+m=9.1*10^-31;     //mass(kg)
+e=1.6*10^-19;     //charge(coulomb)
+
+//Calculation
+n=d*NA/Aw;     //density of electrons
+mew=1/(rho*n*e);    //mobility of electrons(m^2/Vs)
+t=m/(n*e^2*rho);    //average time of collision(s)
+
+//Result
+printf("\n mobility of electrons is %0.3f *10^-2 m V-1 s-1",mew*10^2)
+printf("\n average time of collision is %0.2f *10^-14 s",t*10^14)
diff --git a/3665/CH7/EX7.3/Ex7_3.sce b/3665/CH7/EX7.3/Ex7_3.sce
new file mode 100644
index 000000000..7ea1900a3
--- /dev/null
+++ b/3665/CH7/EX7.3/Ex7_3.sce
@@ -0,0 +1,15 @@
+clc//
+//
+//
+
+//Variable declaration
+P=1.54*10^-8;     //resistance(ohm m)
+n=5.8*10^28;      //number of electrons(per m^3)
+m=9.108*10^-31;     //mass(kg)
+e=1.602*10^-19;     //charge(coulomb)
+
+//Calculation
+t=m/(n*e^2*P);      //relaxation time of conduction electrons(s) 
+
+//Result
+printf("\n relaxation time of conduction electrons is %0.2f *10^-14 s",t*10^14)
diff --git a/3665/CH7/EX7.4/Ex7_4.sce b/3665/CH7/EX7.4/Ex7_4.sce
new file mode 100644
index 000000000..c37ca0146
--- /dev/null
+++ b/3665/CH7/EX7.4/Ex7_4.sce
@@ -0,0 +1,23 @@
+clc//
+//
+//
+
+//Variable declaration
+R=0.06;    //resistance(ohm)
+I=15;      //current(A)
+D=5;     //length(m)
+MA=26.98;       //atomic mass
+rho_s=2.7*10^3;    //density(kg/m^3)
+NA=6.025*10^26;       //avagadro number(per k mol)
+e=1.602*10^-19;     //charge(coulomb)
+
+//Calculation
+n=3*rho_s*NA/MA;     //free electron concentration(electrons/m^2)
+mew=1/(n*e*rho_s*10^-11);     //mobility(m s-1 V-1)
+E=I*R/D;     //electric field(V/m)
+vd=mew*E;    //drift velocity of electrons(m/s)
+
+//Result
+printf("\n free electron concentration is %0.4f *10^29 electrons/m^2",n/10^29)
+printf("\n mobility is %0.3f *10^-3 m s-1 V-1",mew*10^3)
+printf("\n drift velocity of electrons is %0.2f *10^-3 m s-1",vd*10^3)