question_answer

If\[{{P}_{R}}=\]Rankin's Load, \[{{P}_{E}}=\]crippling load by Euler's formula and \[{{P}_{C}}\]crushing load, then Rankin's formula for columns is given as:

A)  \[\frac{1}{{{P}_{E}}}=\frac{1}{{{P}_{R}}}+\frac{1}{{{P}_{C}}}\]   

B)  \[\frac{1}{{{P}_{C}}}=\frac{1}{{{P}_{E}}}+\frac{1}{{{P}_{R}}}\]

C)  \[\frac{1}{{{P}_{R}}}=\frac{1}{{{P}_{E}}}-\frac{1}{{{P}_{C}}}\]    

D)  \[\frac{1}{{{P}_{R}}}=\frac{1}{{{P}_{E}}}+\frac{1}{{{P}_{C}}}\]