Answer:
34.64Gpa
Explanation:
We can calculate the theoretical fracture strenght by,
[tex]\sigma_m = 2\sigma_0 (\frac{\alpha}{\rho})^(1/2)[/tex]
Here we have,
[tex]\sigma_0 =[/tex] Applied stress
[tex]\rho =[/tex]Tip radius
[tex]\alpha =[/tex] lenght of surface crack or half of the lenght of internal crack
Replacing,
[tex]\sigma_m = 2*1200*(\frac{0.25}{1.2*10^{-3}})^(1/2)[/tex]
[tex]\sigma_m = 34641Mpa = 34.64Gpa[/tex]
Therefore the maximum stress at the crack tip is 34.64Gpa