Four vertical columns of the same material, height and weight have the same end condition. The buckling load will be the largest for a column having the cross-section of a/an

A beam has a solid circular cross-section having diameter d. If a section of the beam is subjected to a shear force F the maximum shear stress in the cross-section is given by

A cantilever beam of span 4 m and cross-sectional are 0.3 m wide and 0.4 m deep is subjected to a concentrated load of 10 kN at the free end. Neglecting self-weight, the maximum bending stress at a section 2 m from the free end will be

A simply supported beam AB of span 'l' has a form cross-section throughout. It carries a central concentrated load W and another load which is uniformly distributed over the entire span, its total magnitude being W. The minimum deflection in the beam is