Gere & Goodno — Stresses in Beams (Advanced Topics): Problem 6.2-3

6.2-3 A composite beam consisting of fiberglass faces and a core of particle board has the cross section shown in the figure. The width of the beam is 50 mm, the thickness of the faces is 3 mm, and the thickness of the core is 14 mm. The beam is subjected to a bending moment of 55 N·m acting about the z axis. Find the maximum bending stresses \(\sigma_f\) and \(\sigma_c\) in the faces and the core, respectively, if their respective moduli of elasticity are 28 GPa and 10 GPa.