(Q) An aluminum alloy (E=73GPa) tube A with an outer diameter of 75mm is used to support a 25-m-diameter steel (E=210GPa) rod B, as shown (in the attachement). Determine the minimum thickness t required for the tube if the maximum deflection of the loaded end must be limited to 0.40 mm. I understand if the length of the working puts you off. In that case, can someone please tell me: (a) What deformation compatibility equation to use? (b) How is it that for the steel, the load is 35 kN and the length, area and extension are all given? What I mean is that if we calculate the Young's Modulus using those figures, it does not come out to be 200 GPa. In that case, what force do we use? (c)What is the force on each of the aluminum alloy bars?