Questions & Answers of Failure Theories

The principal stresses at a point inside a solid object are $\sigma_1=100\;\mathrm{MPa}$ $\sigma_2=100\;\mathrm{MPa}$ and $\sigma_3=0\;\mathrm{MPa}$. The yield strength of the material is 200 MPa. The factor of safety calculated using Tresca (maximum shear stress) theory is nT and the factor of safety calculated using von Mises (maximum distortional energy) theory is $n_V$. Which one of the following relations is TRUE?

Which one of the following is the most conservative fatigue failure criterion?

A machine element is subjected to the following bi-axial state of stress: σx=80 MPa; σy=20 MPa; τxy=40 MPa.If the shear strength of the material is 100 MPa, the factor of safety as per Tresca’s maximum shear stress theory is

The uniaxial yield stress of a material is 300 MPa. According to Von mises criterion, the shear yield stress (in MPa) of the material is ______.

Which one of following is NOT correct?