# Chapter 6: Optical Sources LEDs¶

## Example 1: PgNo-277¶

In [1]:
import math

# Initialisation of variables
R=8*math.pow(10,-2) # curve of radius in meter
s=((R+2*r)/(R+r))-1
s_p=s*100 # percentage of strain

# Results
print ('%s %.2f %s' %(" The percentage of strain = ",s_p,"%"))
print ("\n If this condition is maintained the fiber will maintain without any break ")

 The percentage of strain =  0.16 %

If this condition is maintained the fiber will maintain without any break


## Example 2: PgNo-279¶

In [2]:
import math

# initialisation of variables
w=40*math.pow(10,-3) # cable weighing in kg/m
R=20*math.pow(10,-2) # radius of curvature in meter
n=0.19 # co-efficient of friction

 The puttling tension at the exit of an optical cable =  49.173 kg