import math
#variable declaration
F = 8482; # Tensile force in newtons
lo = 0.30; # length of steel wire in cm
Y = 207*10**9; # Youngs modulus of steel Gpa
r = 3*10**-3; # radius of steel wire in m
v = 0.30; # poisson ratio
# Calculations
dl = (F*lo)/float(Y*math.pi*r**2); #elongation in mm
e1 = dl/float(lo); #longitudanl strain
e2 = v*e1 # lateral strain
dr = e2*r; # lateral contraction in m
# Result
print'Elongation = %3.3f'%(dl*10**3),'mm';
print'Lateral contraction = %3.2f '%(dr*10**6),'um';
import math
#variable declaration
P = 400; # tensile force in newtons
d = 6*10**-3; # diameter of steel rod m
# Calculations
r =d/float(2);
E_stress = (P)/float((math.pi/float(4))*d*d); #e_stress in N/m**2
#Result
print'Engineering stress = %3.2f '%(E_stress*10**-6),'MPa';
import math
#variable declaration
Lf = 42.3; #guage length after strain mm
Lo = 40; # guage length in mm
# Calculations
e = ((Lf - Lo)/float(Lo))*100 #Engineering Strain in %
#Result
print'Percentage of elongation = %3.2f '%e,'%';
import math
#variable declaration
dr = 12.8; # original diameter of steel wire in mm
df = 10.7; # diameter at fracture in mm
# Calculations
percent_red = (((math.pi*dr*dr) - (math.pi*df*df))/float(math.pi*dr*dr))*100; #Percent reduction in area in %
# Result
print'Percent reduction in area = %3.1f'%percent_red,'%';