The step-rod shown in the figure is made of an aluminum alloy (elastic modulus 70 GPa), and is subjected to an axial load of 10 kN. A portion of the stress-strain diagram of this alloy is also shown. Determine the approximate elongation of the rod when this load is applied. What is the elastic recovery when the load is removed? (MPa) 60 50 Oy=40 20 mm 15 mm 10 KN 10 kN 600 mm 400 mm parallel 30 20 10 BC G (mm/mm) 0 0.02 0.04 0.06 0.08 0.12 EOG