initial commit / add all books

34 files changed, 333 insertions, 0 deletions

diff --git a/2333/CH6/EX6.1/1.sce b/2333/CH6/EX6.1/1.sce
new file mode 100755
index 000000000..7b991dac0
--- /dev/null
+++ b/2333/CH6/EX6.1/1.sce
@@ -0,0 +1,15 @@
+clc
+    
+// Given that
+mu1 = 1.42 // refractive index for core
+mu2 = 1.40 // refractive index for cladding
+// Sample Problem 1 on page no. 254
+printf("\n # PROBLEM 1 # \n")
+NA = sqrt(mu1^2 - mu2^2)
+theta_0 = asin(NA) * (180 / %pi)
+theta_deg = floor(theta_0)
+theta_fract = theta_0 - floor(theta_0)
+theta_min = theta_fract*60
+printf("\n Standard formula used \n NA = sqrt(mu1^2 - mu2^2). \n theta_0 = asin(NA) * (180 / pi). \n")
+printf("\n  \n Numerical aperture = %f,\n Maximum incidence angle = %d degree %d min.",NA,theta_deg,theta_min)
+
diff --git a/2333/CH6/EX6.1/1.txt b/2333/CH6/EX6.1/1.txt
new file mode 100755
index 000000000..398e283e4
--- /dev/null
+++ b/2333/CH6/EX6.1/1.txt
@@ -0,0 +1,9 @@
+ # PROBLEM 1 # 

+

+ Standard formula used 

+ NA = sqrt(mu1^2 - mu2^2). 

+ theta_0 = asin(NA) * (180 / pi). 

+

+  

+ Numerical aperture = 0.237487,

+ Maximum incidence angle = 13 degree 44 min.
\ No newline at end of file
diff --git a/2333/CH6/EX6.10/10.sce b/2333/CH6/EX6.10/10.sce
new file mode 100755
index 000000000..0441c8054
--- /dev/null
+++ b/2333/CH6/EX6.10/10.sce
@@ -0,0 +1,9 @@
+clc 
+// Given that
+NA = 0.3 // numerical aperture of fiber
+d = 200 // core diameter in micro meter
+lambda = 0.9 // wavelength of propagating light in micro meter
+// Sample Problem 10 on page no. 268
+printf("\n # PROBLEM 10 # \n")
+N_max = 2*(d/2)^2*%pi^2*NA^2/lambda^2
+printf("\n Total number of propagating modes are %d.",N_max)
diff --git a/2333/CH6/EX6.10/10.txt b/2333/CH6/EX6.10/10.txt
new file mode 100755
index 000000000..589405c6f
--- /dev/null
+++ b/2333/CH6/EX6.10/10.txt
@@ -0,0 +1,3 @@
+# PROBLEM 10 # 

+

+ Total number of propagating modes are 21932.
\ No newline at end of file
diff --git a/2333/CH6/EX6.11/11.sce b/2333/CH6/EX6.11/11.sce
new file mode 100755
index 000000000..704cec14e
--- /dev/null
+++ b/2333/CH6/EX6.11/11.sce
@@ -0,0 +1,13 @@
+clc

+// given that

+

+d = 9 // Diameter of ore of wire in mm

+P_b = 180 // Threshold optical power for Brillouin scattering in mW

+P_r = 1.9 // Threshold optical power for Raman scattering  W

+nu = 1 // Bandwidth in GHz

+ // Sample Problem 11 on page no. 278

+printf("\n # PROBLEM 11 # \n")

+ratio = P_b*1e-3/P_r // Calculation of ratios of powers

+lambda = ratio*5.9*1e-2*(d*1e-3)^2/(4.4*1e-3*(d*1e-3)^2) // Calcualtion of wavelength

+printf("\n Standard formula used \n P_b = 4.4*1e-3*d^2*lambda^2*alpha.\nP_r = 5.9*1e-3*d^2*lambda^2*alpha \n")

+printf("\n wavelength of laser is %fmicron. ",lambda)

diff --git a/2333/CH6/EX6.11/11.txt b/2333/CH6/EX6.11/11.txt
new file mode 100755
index 000000000..00a911723
--- /dev/null
+++ b/2333/CH6/EX6.11/11.txt
@@ -0,0 +1,7 @@
+ # PROBLEM 11 # 

+

+ Standard formula used 

+ P_b = 4.4*1e-3*d^2*lambda^2*alpha.

+P_r = 5.9*1e-3*d^2*lambda^2*alpha 

+

+ wavelength of laser is 1.270335micron. 
\ No newline at end of file
diff --git a/2333/CH6/EX6.12/12.sce b/2333/CH6/EX6.12/12.sce
new file mode 100755
index 000000000..f7221fe8a
--- /dev/null
+++ b/2333/CH6/EX6.12/12.sce
@@ -0,0 +1,10 @@
+clc 
+// Given that
+P_in = 100 // power of input signal in mW
+P_out = 50 // power of output signal in mW
+// Sample Problem 12 on page no. 280
+printf("\n # PROBLEM 12 # \n")
+alpha = (10 * log10(P_in / P_out))//calculation for absorption coefficient
+printf("\n Standard formula used \n alpha=10/L*log(Pi/Po).\n")
+printf("\n Attenuation loss is %f dB. ",alpha)
+
diff --git a/2333/CH6/EX6.12/12.txt b/2333/CH6/EX6.12/12.txt
new file mode 100755
index 000000000..e3b901c80
--- /dev/null
+++ b/2333/CH6/EX6.12/12.txt
@@ -0,0 +1,6 @@
+# PROBLEM 12 # 

+

+ Standard formula used 

+ alpha=10/L*log(Pi/Po).

+

+ Attenuation loss is 3.010300 dB. 
\ No newline at end of file
diff --git a/2333/CH6/EX6.13/13.sce b/2333/CH6/EX6.13/13.sce
new file mode 100755
index 000000000..c71f376c7
--- /dev/null
+++ b/2333/CH6/EX6.13/13.sce
@@ -0,0 +1,10 @@
+clc 
+// Given that
+l = 150 // length of fiber in meter
+P_in = 10 // power of input signal in micro Watt
+P_out = 8 // power of output signal in micro Watt
+// Sample Problem 13 on page no. 280
+printf("\n # PROBLEM 13 # \n")
+alpha = (10 * log10(P_in / P_out))/l //calculation for absorption coefficient
+printf("\n Standard formula used \n alpha=10/L*log(Pi/Po).\n")
+printf("\n Attenuation loss is %f dB/m. ",alpha)
diff --git a/2333/CH6/EX6.13/13.txt b/2333/CH6/EX6.13/13.txt
new file mode 100755
index 000000000..6460c2d1e
--- /dev/null
+++ b/2333/CH6/EX6.13/13.txt
@@ -0,0 +1,6 @@
+# PROBLEM 13 # 

+

+ Standard formula used 

+ alpha=10/L*log(Pi/Po).

+

+ Attenuation loss is 0.006461 dB/m. 
\ No newline at end of file
diff --git a/2333/CH6/EX6.14/14.sce b/2333/CH6/EX6.14/14.sce
new file mode 100755
index 000000000..8929a6d1e
--- /dev/null
+++ b/2333/CH6/EX6.14/14.sce
@@ -0,0 +1,11 @@
+clc 
+    
+// Given that
+l = 1.5 // length of fiber in kilo meter
+P_in = 1 // let power of input signal is unity
+P_out = 1/4 // power of output signal in micro Watt
+// Sample Problem 14 on page no. 281
+printf("\n # PROBLEM 14 # \n")
+alpha = (10 * log10(P_in / P_out))/l //calculation for absorption coefficient
+printf("\n Standard formula used \n alpha=10/L*log(Pi/Po).\n")
+printf("\n Attenuation loss is %d dB/km. ",alpha)
diff --git a/2333/CH6/EX6.14/14.txt b/2333/CH6/EX6.14/14.txt
new file mode 100755
index 000000000..10c08bcef
--- /dev/null
+++ b/2333/CH6/EX6.14/14.txt
@@ -0,0 +1,6 @@
+# PROBLEM 14 # 

+

+ Standard formula used 

+ alpha=10/L*log(Pi/Po).

+

+ Attenuation loss is 4 dB/km. 
\ No newline at end of file
diff --git a/2333/CH6/EX6.15/15.sce b/2333/CH6/EX6.15/15.sce
new file mode 100755
index 000000000..cf0a3d7c4
--- /dev/null
+++ b/2333/CH6/EX6.15/15.sce
@@ -0,0 +1,11 @@
+clc 
+// Given that
+l = 10 // length of fiber in kilo meter
+P_in = 900 // Power of input signal in micro watt
+alpha = 2.3 // attenuation loss in dB
+// Sample Problem 15 on page no. 281
+printf("\n # PROBLEM 15 # \n")
+P_out = P_in*10^(-alpha) // Power at output in microwatt
+printf("\n Standard formula used \n alpha=10/L*log(Pi/Po).\n")
+printf("\n Power at output end is %f micro Watt.",P_out)
+// Answer given in book is 1.79 micro Watt
diff --git a/2333/CH6/EX6.15/15.txt b/2333/CH6/EX6.15/15.txt
new file mode 100755
index 000000000..7113907cd
--- /dev/null
+++ b/2333/CH6/EX6.15/15.txt
@@ -0,0 +1,7 @@
+ 

+ # PROBLEM 15 # 

+

+ Standard formula used 

+ alpha=10/L*log(Pi/Po).

+

+ Power at output end is 4.510685 micro Watt.
\ No newline at end of file
diff --git a/2333/CH6/EX6.16/16.sce b/2333/CH6/EX6.16/16.sce
new file mode 100755
index 000000000..3f8746baf
--- /dev/null
+++ b/2333/CH6/EX6.16/16.sce
@@ -0,0 +1,11 @@
+clc 
+// Given that
+l = 6 // length of fiber in kilo meter
+mu1 = 1.48 // refractive index for core
+NA = 0.28 // Numerical aperture
+c = 3e8 // speed of light in m/sec
+// Sample Problem 16 on page no. 284
+printf("\n # PROBLEM 16 # \n")
+t = l*1e3*(NA)^2/(2*c*mu1)
+printf("\n Time taken by light pulse is %f nsec.",t*1e9)
+
diff --git a/2333/CH6/EX6.16/16.txt b/2333/CH6/EX6.16/16.txt
new file mode 100755
index 000000000..10fec21c4
--- /dev/null
+++ b/2333/CH6/EX6.16/16.txt
@@ -0,0 +1,3 @@
+# PROBLEM 16 # 

+

+ Time taken by light pulse is 529.729730 nsec.
\ No newline at end of file
diff --git a/2333/CH6/EX6.17/17.sce b/2333/CH6/EX6.17/17.sce
new file mode 100755
index 000000000..e5f978afd
--- /dev/null
+++ b/2333/CH6/EX6.17/17.sce
@@ -0,0 +1,15 @@
+clc 
+// Given that
+l = 8 // length of fiber in kilo meter
+mu1 = 1.50 // refractive index for core
+delta = 2/100 // relative refractive index
+c = 3e8 // speed of light in m/sec
+// Sample Problem 17 on page no. 285
+printf("\n # PROBLEM 17 # \n")
+t = l*1e3*mu1*delta/c * 1e9
+sigma = t/(2*sqrt(3))
+BT_max = 1/(2*t) // 
+Length = BT_max*1e3*l
+
+printf("\n Time taken by light pulse is %f nsec. \n RPM pulse is %f nsec",t,sigma)
+printf("\n Maximum bit rate is %f M bit/sec \n Bandwidth length product is %dMHz km", BT_max*1e3,Length)
diff --git a/2333/CH6/EX6.17/17.txt b/2333/CH6/EX6.17/17.txt
new file mode 100755
index 000000000..2b29bdaa6
--- /dev/null
+++ b/2333/CH6/EX6.17/17.txt
@@ -0,0 +1,6 @@
+# PROBLEM 17 # 

+

+ Time taken by light pulse is 800.000000 nsec. 

+ RPM pulse is 230.940108 nsec

+ Maximum bit rate is 0.625000 M bit/sec 

+ Bandwidth length product is 5MHz km 
\ No newline at end of file
diff --git a/2333/CH6/EX6.2/2.sce b/2333/CH6/EX6.2/2.sce
new file mode 100755
index 000000000..45ec4e2e6
--- /dev/null
+++ b/2333/CH6/EX6.2/2.sce
@@ -0,0 +1,12 @@
+clc 
+// Given that
+mu1 = 1.36 // refractive index for core
+del_mu = 0.025 // relative refractive index
+
+// Sample Problem  on page no. 255
+printf("\n # PROBLEM 2 # \n")
+mu2 = mu1*(1-del_mu) // refractive index of cladding
+NA = mu1*sqrt(2*del_mu)
+theta_0 = asin(NA) * (180 / %pi)
+printf("\n Standard formula used \n theta_c = asin(mu2 / mu1) * (180 / pi). \n NA = sqrt(mu1^2 - mu2^2). \n theta_0 = asin(NA) * (180 / pi). \n")
+printf("\n Refractive index of cladding is %f. \n Numerical aperture is %f.\n Acceptance angle is %f degree.",mu2,NA,theta_0)
diff --git a/2333/CH6/EX6.2/2.txt b/2333/CH6/EX6.2/2.txt
new file mode 100755
index 000000000..49155fd29
--- /dev/null
+++ b/2333/CH6/EX6.2/2.txt
@@ -0,0 +1,10 @@
+# PROBLEM 2 # 

+

+ Standard formula used 

+ theta_c = asin(mu2 / mu1) * (180 / pi). 

+ NA = sqrt(mu1^2 - mu2^2). 

+ theta_0 = asin(NA) * (180 / pi). 

+

+ Refractive index of cladding is 1.326000. 

+ Numerical aperture is 0.304105.

+ Acceptance angle is 17.704341 degree.
\ No newline at end of file
diff --git a/2333/CH6/EX6.3/3.sce b/2333/CH6/EX6.3/3.sce
new file mode 100755
index 000000000..702125cdf
--- /dev/null
+++ b/2333/CH6/EX6.3/3.sce
@@ -0,0 +1,15 @@
+clc 
+// Given that
+mu2 = 1.59 // refractive index for cladding
+NA = 0.2 // Numerical aperture
+mu_water = 1.33 // refractive index of water
+del_mu = 0.025 // relative refractive index
+
+// Sample Problem 3 on page no. 256
+printf("\n # PROBLEM 3 # \n")
+mu1 = sqrt(NA^2+mu2^2) // refractive index of cladding
+NA_w = sqrt(mu1^2 - mu2^2)/mu_water // Numerical aperture for water
+theta_0 = asin(NA_w) * (180 / %pi) // Acceptance angle of fiber in water
+printf("\n Standard formula used \n theta_c = asin(mu2 / mu1) * (180 / pi). \n NA = sqrt(mu1^2 - mu2^2). \n theta_0 = asin(NA) * (180 / pi). \n")
+printf("\n Acceptance angle of fiber in water is %f degree.",theta_0)
+
diff --git a/2333/CH6/EX6.3/3.txt b/2333/CH6/EX6.3/3.txt
new file mode 100755
index 000000000..25a6efd87
--- /dev/null
+++ b/2333/CH6/EX6.3/3.txt
@@ -0,0 +1,8 @@
+# PROBLEM 3 # 

+

+ Standard formula used 

+ theta_c = asin(mu2 / mu1) * (180 / pi). 

+ NA = sqrt(mu1^2 - mu2^2). 

+ theta_0 = asin(NA) * (180 / pi). 

+

+ Acceptance angle of fiber in water is 8.648713 degree.
\ No newline at end of file
diff --git a/2333/CH6/EX6.4/4.sce b/2333/CH6/EX6.4/4.sce
new file mode 100755
index 000000000..4802e7e73
--- /dev/null
+++ b/2333/CH6/EX6.4/4.sce
@@ -0,0 +1,16 @@
+clc 
+// Given that
+mu1 = 1.55 // refractive index for core
+mu2 = 1.50 // refractive index for cladding
+d = 50 // core diameter in micro meter
+// Sample Problem 4 on page no. 256
+printf("\n # PROBLEM 4 # \n")
+
+NA = sqrt(mu1^2 - mu2^2) // numerical aperture 
+theta_c = asin(mu2 / mu1) * (180 / %pi) // critical angle in degree
+theta_0 = asin(NA) * (180 / %pi) // Acceptance angle in degree
+x= d*1e-6*tan(theta_c*%pi/180) // distance travelled between two successive collisions
+
+N = 1/x // No. of reflections per meter
+printf("\n Standard formula used \n theta_c = asin(mu2 / mu1) * (180 / pi). \n NA = sqrt(mu1^2 - mu2^2). \n theta_0 = asin(NA) * (180 / pi). \n")
+printf("\n Numerical aperture = %f,\n Acceptance angle is %f degree.\n No. of reflections per meter is %d",NA,theta_0,N)
diff --git a/2333/CH6/EX6.4/4.txt b/2333/CH6/EX6.4/4.txt
new file mode 100755
index 000000000..9d97484f1
--- /dev/null
+++ b/2333/CH6/EX6.4/4.txt
@@ -0,0 +1,10 @@
+# PROBLEM 4 # 

+

+ Standard formula used 

+ theta_c = asin(mu2 / mu1) * (180 / pi). 

+ NA = sqrt(mu1^2 - mu2^2). 

+ theta_0 = asin(NA) * (180 / pi). 

+

+ Numerical aperture = 0.390512,

+ Acceptance angle is 22.986391 degree.

+ No. of reflections per meter is 5206
\ No newline at end of file
diff --git a/2333/CH6/EX6.5/5.sce b/2333/CH6/EX6.5/5.sce
new file mode 100755
index 000000000..93056de81
--- /dev/null
+++ b/2333/CH6/EX6.5/5.sce
@@ -0,0 +1,11 @@
+clc 
+// Given that
+mu1 = 1.45 // refractive index for core
+mu2 = 1.40 // refractive index for cladding
+mu = 1 // refractive index for air
+// Sample Problem 5 on page no. 256
+printf("\n # PROBLEM 5 # \n")
+theta_c = asin(mu2 / mu1) * (180 / %pi) // critical angle in degree
+theta_c_ = asin(mu/mu2) * (180 / %pi) // Acceptance angle in degree
+printf("\n Standard formula used \n theta_c = asin(mu2 / mu1) * (180 / pi). \n NA = sqrt(mu1^2 - mu2^2). \n theta_0 = asin(NA) * (180 / pi). \n")
+printf("\n Critical angle at the core - cladding boundary is %f degree \n Critical angle at cladding - air boundary is %f degree",theta_c,theta_c_)
diff --git a/2333/CH6/EX6.5/5.txt b/2333/CH6/EX6.5/5.txt
new file mode 100755
index 000000000..2ed94214a
--- /dev/null
+++ b/2333/CH6/EX6.5/5.txt
@@ -0,0 +1,9 @@
+# PROBLEM 5 # 

+

+ Standard formula used 

+ theta_c = asin(mu2 / mu1) * (180 / pi). 

+ NA = sqrt(mu1^2 - mu2^2). 

+ theta_0 = asin(NA) * (180 / pi). 

+

+ Critical angle at the core - cladding boundary is 74.909815 degree 

+ Critical angle at cladding - air boundary is 45.584691 degree
\ No newline at end of file
diff --git a/2333/CH6/EX6.6/6.sce b/2333/CH6/EX6.6/6.sce
new file mode 100755
index 000000000..057aee8c1
--- /dev/null
+++ b/2333/CH6/EX6.6/6.sce
@@ -0,0 +1,17 @@
+clc 
+// Given that
+mu1 = 1.50 // refractive index for core
+mu2 = 1.48 // refractive index for cladding
+a = 25 // core radius in micro meter
+lambda = 830 // wavelength of propagating light in nano meter
+al = 2 // for parabolic profile
+// Sample Problem 6 on page no. 263
+printf("\n # PROBLEM 6 # \n")
+del = (mu1-mu2)/mu1 
+N_graded = (al/(al+2))*(2*%pi*a*1e-6/(lambda*1e-9))^2 * mu1^2 * del // Number of modes for graded
+N_step = (2*%pi*a*1e-6/(lambda*1e-9))^2 * (mu1^2 - mu2^2)/2 // number of modes for step graded
+ratio = (N_step / N_graded)
+printf("\n Number of modes in graded index fiber is %d.",N_graded)
+printf("\n Number of modes in Step graded fiber is %d.",N_step)
+printf("\n Approximate ratio of number of modes in different grade is %d.",ceil(ratio))
+
diff --git a/2333/CH6/EX6.6/6.txt b/2333/CH6/EX6.6/6.txt
new file mode 100755
index 000000000..5855fbf74
--- /dev/null
+++ b/2333/CH6/EX6.6/6.txt
@@ -0,0 +1,6 @@
+ 

+ # PROBLEM 6 # 

+

+ Number of modes in graded index fiber is 537.

+ Number of modes in Step graded fiber is 1067.

+ Approximate ratio of number of modes in different grade is 2. 
\ No newline at end of file
diff --git a/2333/CH6/EX6.7/7.sce b/2333/CH6/EX6.7/7.sce
new file mode 100755
index 000000000..3eb8f6521
--- /dev/null
+++ b/2333/CH6/EX6.7/7.sce
@@ -0,0 +1,13 @@
+clc 
+// Given that
+mu1 = 1.566 // refractive index for core
+mu2 = 1.56 // refractive index for cladding
+d = 50 // core diameter in micro meter
+lambda = 0.84 // wavelength of propagating light in micro meter
+// Sample Problem 7 on page no. 265
+printf("\n # PROBLEM 7 # \n")
+v = %pi*d*sqrt(mu1^2 - mu2^2)/lambda  // cut off number
+N_max = v^2/2 // maximum number of modes
+printf("\n Cut off parameter of fiber is %f. \n Maximum number of modes is %d.",v,N_max)
+
+    
diff --git a/2333/CH6/EX6.7/7.txt b/2333/CH6/EX6.7/7.txt
new file mode 100755
index 000000000..abd9ad69c
--- /dev/null
+++ b/2333/CH6/EX6.7/7.txt
@@ -0,0 +1,4 @@
+# PROBLEM 7 # 

+

+ Cut off parameter of fiber is 25.610066. 

+ Maximum number of modes is 327.
\ No newline at end of file
diff --git a/2333/CH6/EX6.8/8.sce b/2333/CH6/EX6.8/8.sce
new file mode 100755
index 000000000..43dd5098a
--- /dev/null
+++ b/2333/CH6/EX6.8/8.sce
@@ -0,0 +1,13 @@
+clc 
+// Given that
+mu1 = 1.55 // refractive index for core
+v_max = 2.405 // Maximum cut off number
+d = 10 // core diameter in micro meter
+lambda = 1.8 // wavelength of propagating light in micro meter
+// Sample Problem 8 on page no. 266
+printf("\n # PROBLEM 8 # \n")
+NA = v_max*lambda/(%pi*d)
+delta = 0.5*(NA/mu1)^2 // Normalized index difference
+mu2 = mu1*(1- delta) // refractive index of cladding
+theta_max = asin(NA)*180/%pi // maximum acceptance angle in degree
+printf("\n Required maximum value of normalized difference is %f. \n Refractive index of cladding is %f. \n Maximum acceptance angle is %f degree.",delta,mu2,theta_max)
diff --git a/2333/CH6/EX6.8/8.txt b/2333/CH6/EX6.8/8.txt
new file mode 100755
index 000000000..1ef0d40ad
--- /dev/null
+++ b/2333/CH6/EX6.8/8.txt
@@ -0,0 +1,6 @@
+ 

+ # PROBLEM 8 # 

+

+ Required maximum value of normalized difference is 0.003952. 

+ Refractive index of cladding is 1.543875. 

+ Maximum acceptance angle is 7.920351 degree.
\ No newline at end of file
diff --git a/2333/CH6/EX6.9/9.sce b/2333/CH6/EX6.9/9.sce
new file mode 100755
index 000000000..92c0e028c
--- /dev/null
+++ b/2333/CH6/EX6.9/9.sce
@@ -0,0 +1,14 @@
+clc 
+// Given that
+mu1 = 1.466 // refractive index for core
+mu2 = 1.46 // refractive index for cladding
+lambda = 1200 // wavelength of light in nano meter
+V = 2.405 // cut off parameter
+// Sample Problem 9 on page no. 267
+printf("\n # PROBLEM 9 # \n")
+t = V*lambda*1e-9/(2*%pi*sqrt(mu1^2-mu2^2)) // maximum radius of fiber
+theta_c = asin(mu2 / mu1) * (180 / %pi)
+NA = sqrt(mu1^2 - mu2^2)
+theta_0 = asin(NA) * (180 / %pi)
+printf("\n Standard formula used \n theta_c = asin(mu2 / mu1) * (180 / pi). \n NA = sqrt(mu1^2 - mu2^2). \n theta_0 = asin(NA) * (180 / pi). \n")
+printf("\n Maximum radius allowed for fiber is %f micro meter \nCritical angle = %f degree. \n Numerical aperture = %f,\n Maximum incidence angle = %f degree.",t*1e6,theta_c,NA,theta_0)
diff --git a/2333/CH6/EX6.9/9.txt b/2333/CH6/EX6.9/9.txt
new file mode 100755
index 000000000..5065b9fb2
--- /dev/null
+++ b/2333/CH6/EX6.9/9.txt
@@ -0,0 +1,11 @@
+# PROBLEM 9 # 

+

+ Standard formula used 

+ theta_c = asin(mu2 / mu1) * (180 / pi). 

+ NA = sqrt(mu1^2 - mu2^2). 

+ theta_0 = asin(NA) * (180 / pi). 

+

+ Maximum radius allowed for fiber is 3.466600 micro meter 

+Critical angle = 84.814454 degree. 

+ Numerical aperture = 0.132499,

+ Maximum incidence angle = 7.614027 degree.
\ No newline at end of file