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Q1. Mohr's circle for stress and strain The aircraft fuselage illustrated in Figure Q1 with internal radius of 0.5 m and a thickness of 5 mm, is subject to a combined internal pressure of 1N/mm² and Torque of 10000kNm in the direction shown: T R=0.5 m t=5 mm Oyy Txy 00 Oxx Figure Q1 – Rectangular strain gauge rosette. (a) Calculate normal and shear stresses on an element of the fuselage skin illustrated in Figure Q1, and produce a sketch to illustrate your results. (61 (b) Draw the Mohr circle. [2] (c) Calculate the principal stresses and their directions. [4] (d) Calculate the orientation and magnitude of the maximum shear stress and co- existent normal stress [4] Given that the yield strength is 90 N/mm2 (e) Determine the factor of safety against yielding using the von Mises criterion: oi = 0 +0 -0,02 [2] Given Tresca failure criterion Oy= 01 (1) Determine the factor of safety against yield. Comment on the cause of any difference between Tresca and Von Mises results. [2] Continued overleaf Page 2 of 5