Question

Assertion (A): Rankine's theory is generally used for finding out the buckling load of intermediate columns.
Reason (R): Euler's theory gives higher values for buckling loads in intermediate columns.

• A. both A and R are true and R is the correct explanation of A
• B. both A and R are true but R is not a correct explanation of A
• C. A is true but R is false
• D. A is false but R is true

Answer 1

The correct option is B both A and R are true but R is not a correct explanation of A

For intermediate columns, the effect of both crushing and buckling is to be considered as none of these alone gives the satisfactory results. Load by Rankine's formula is given as,
$\frac{1}{P_R}=\frac{1}{P_e}+\frac{1}{P_c}$
where, $P_R$ is Rankine's load
$P_c$ is crushing load and
$P_e$ is buckling load
So, Rankine's load considers the effect of both crushing and buckling, hence used for intermediate columns.