고체역학 (Beer) — Pure Bending: Problem 4.44

4.40 A steel bar (\(E_s = 210 \text{ GPa}\)) and an aluminum bar (\(E_a = 70 \text{ GPa}\)) are bonded together to form the composite bar shown. Determine the maximum stress in (a) the aluminum, (b) the steel, when the bar is bent about a horizontal axis, with \(M = 60 \text{ N}\cdot\text{m}\). 4.44 For the composite beam in Prob. 4.40, determine the radius of curvature caused by the couple of moment \(60 \text{ N}\cdot\text{m}\).