Question

The ratio of the theoretical critical buckling load for a column with fixed ends to that of another column with the same dimesions and material, but with pinned ends, is equal to

• A. 0.5
• B. 1.0
• C. 2.0
• D. 4.0

Answer 1

The correct option is D 4.0

$P=\frac{{\pi }^{2}EI}{l_{eff}^2}$
$P{l}_{eff}^2=$ constant
$\Rightarrow P_1{l}_{eff}^2=P_2{l}_2{}_{eff}^2$
$\frac{P_1}{P_2}={\left(\frac{l_2}{l_1}\right)}_{eff}^2={\left(\frac{l}{l/2}\right)}^2=4$