A composite assembly consisting of a steel [G = 80GPa] core (2) connected by rigid plates at the ends of an aluminum [G= 28 GPa] tube (1) is shown. The cross-sectional dimensions of the assembly are shown in the second figure. Assume L = 350 mm,D₁ = 57, d₁ = 30 mm, d₂ = 25 mm. If a torque of T =600 N-m is applied to the composite assembly,determine (a) the maximum shear stress in the aluminumtube and in the steel core. (b) the rotation angle of end B relative to end A.

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