QUESTION 2 A thick-walled cylinder has an internal and external diameter of 100 and 200 mm, respectively. The cylinder material has a yield strength of 200 MPa. When the internal working pressure is at 120 MPa, the cylinder material is found to have yielded based on the Maximum-shear-stress theory (Tresca). The open-ends condition is considered in the analysis. (a) Determine the required externally applied pressure such that the wall material at the inner surface of the cylinder is at the onset (start) of yielding, based on the Tresca yield criterion. (6 marks) (b) Draw the variations of the hoop stress and radial stress across the thickness of the wall for the loading in part (a). Indicate the magnitude of the stresses at both the inner and outer layers of the cylinder. (2 marks) (c) Draw the locus of the Tresca criterion in the principal stress axes, and indicate the operating stress condition.- (2 marks)