A solid round bar of aluminum having diameter d (see figure) is compressed by an axial force P = 60 kN. The bar has pinned supports and is made of alloy 6061-T6.
(a) If the diameter d = 30 mm, what is maximum allowable length of the bar?
(b) If the length L = 0.6 m, what is the minimum required Diameter dmin?
(Convert the given data to USCS units, determine the required quantities, and the convert back to SI units.)