The 'stiffness' of a simply supported beam at midspan against transverse unit load is:
Choose the correct answer
k = 3EI/L³ (cantilever formula)
k = 48EI/L³ — inverse of midspan deflection δ = PL³/48EI for simply supported beam
k = EI/L
k = PL/AE (axial stiffness)
Correct Answer
B. k = 48EI/L³ — inverse of midspan deflection δ = PL³/48EI for simply supported beam
AI Detailed Explanation & IS Code Reference
Unlock the reasoning, formula path and code-linked notes inside your student dashboard.
Stiffness k = F/δ = 1/flexibility coefficient f₁₁. For SS beam under central unit load: δ_centre = 1×L³/(48EI). So k = 48EI/L³. Flexibility method: f₁₁ = L³/(48EI). Used in: SDOF dynamic model of bridges, beam vibration. Compare: cantilever stiffness at tip = 3EI/L³.
ScoreCardAI links this solution with subject, topic and difficulty signals so your scorecard can identify weak areas after a full mock test.
Practice more Civil Engineering questions
This MCQ belongs to JE Level Premium Test Series. Full tests include timed attempts, rank comparison and subject-wise analysis.