Question 7 A delta strain gauge rosette (60° angles between gauges) bonded to a magnesium alloy component, measured microstrain readings of 300, -240 and 60. Determine the principal strains and from them the principal stresses and the maximum shear stress at this point on the component (a) using analytical relationships and (b) by using Mohr's circles for strain and stress. The relevant material properties are: E = 80 x 10° N/m², v = 0.3. (20 marks)

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