w#3 PROBLEM 3 GIVEN: CEIE 310 A trimetallic bar is uniformly compressed by an axial force P = 40 kN applied through a rigid end plate (see figure). The bar consists of a circular steel core surrounded by brass and copper tubes. The steel core has diameter 30 mm, the brass tube has outer diameter 45 mm and the copper tube has outer diameter 60 mm. The corresponding moduli of elasticity are E, = 210 GP E 100 GPa, and E = 120 GPa. Calculate the compressive stresses σ, σ, and σ, in the steel, brass, and copper, respectively, due to the force P. FIND: σs, Ob; Oc Copper tube Brass tube P=40 kN Steel core 30 mm 45 mm 60 mm