Difficulty: Easy
Correct Answer: All of the above (area through I, length, least radius of gyration, and E)
Explanation:
Introduction / Context:Euler’s formula for long columns shows how geometry, material stiffness, and end conditions jointly govern buckling strength. Understanding each parameter's role is essential in member sizing.
Given Data / Assumptions:
Concept / Approach:Critical load scales linearly with E and I, and inversely with the square of effective length (K * L). Since I involves area A and radius k, area influences Pcr through the second moment of area. Thus multiple properties simultaneously affect buckling.
Step-by-Step Solution:
Write Euler: Pcr = π^2 * E * I / (K * L)^2.Substitute I = A * k^2 → Pcr ∝ E * A * k^2 / (K^2 * L^2).Identify dependencies: E, A, k (least), and L (with end condition factor K).Therefore, all listed geometric and material factors matter.Verification / Alternative check:Comparing two sections with same area but different k (e.g., solid vs thin-walled tube) shows different Pcr, confirming dependence on k in addition to A.
Why Other Options Are Wrong:
Common Pitfalls:Equating larger area with higher buckling load without considering how area is distributed (k).
Final Answer:All of the above (area through I, length, least radius of gyration, and E)
Discussion & Comments