3 files changed, 52 insertions, 0 deletions
diff --git a/3665/CH12/EX12.1/Ex12_1.sce b/3665/CH12/EX12.1/Ex12_1.sce
new file mode 100644
index 000000000..4f3f96aa0
--- /dev/null
+++ b/3665/CH12/EX12.1/Ex12_1.sce
@@ -0,0 +1,19 @@
+clc//
+//
+//
+
+//Variable declaration
+e=1.6*10^-19;     //charge(coulomb)
+h=6.6*10^-34;     //planck's constant(J sec)
+c=3*10^8;     //velocity of light(m/sec)
+lamda=6943*10^-10;     //wavelength(m)
+k=8.61*10^-5;
+T=300;    //temperature(K)
+
+//Calculation
+dE=h*c/(e*lamda);
+N2byN1=exp(-dE/(k*T));     //relative population
+
+//Result
+printf("\n relative population is %0.4f *10^-30",N2byN1*10^30)
+printf("\n answer given in the book is wrong")
diff --git a/3665/CH12/EX12.2/Ex12_2.sce b/3665/CH12/EX12.2/Ex12_2.sce
new file mode 100644
index 000000000..353be8717
--- /dev/null
+++ b/3665/CH12/EX12.2/Ex12_2.sce
@@ -0,0 +1,15 @@
+clc//
+//
+//
+
+//Variable declaration
+a1=4*10^-3;      //diameter(m)
+a2=6*10^-3;      //diameter(m)
+d1=1;     //distance(m)
+d2=2;     //distance(m)
+
+//Calculation
+theta=(a2-a1)/(2*(d2-d1));     //divergence(radian)
+
+//Result
+printf("\n divergence is %0.3f milli radian",theta*10^3)
diff --git a/3665/CH12/EX12.3/Ex12_3.sce b/3665/CH12/EX12.3/Ex12_3.sce
new file mode 100644
index 000000000..b09b3d599
--- /dev/null
+++ b/3665/CH12/EX12.3/Ex12_3.sce
@@ -0,0 +1,18 @@
+clc//
+//
+//
+
+//Variable declaration
+s=1*10^-3;    //size(m)
+l=1*10^-3;    //length(m)
+lamda=650*10^-9;    //wavelength(m)
+
+//Calculation
+tantheta=(l/2)/s;     
+theta=atan(tantheta);    //angle(radian)
+sintheta=(sin(theta));
+
+ss=0.6*lamda/sintheta;     //spot size(m)
+
+//Result
+printf("\n spot size is %0.3f micro m",ss*10^6)