UPSC Civil Service Exam Questions - Engineering

Q1:

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 solid square

B thin hollow circle

C solid circle

D I

ANS:A - solid square

The moment of inertia is maximum for the hollow circular section because the maximum mass, in this case, lies away from the centroidal axis as compared to all other cross sections.

Hence, the load-carrying capacity is maximum for a hollow circular section.