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Beam theory: meaning of point of contraflexure (inflection point) On a bending moment diagram for a beam, identify what occurs at the point of contraflexure.

Q: Beam theory: meaning of point of contraflexure (inflection point) On a bending moment diagram for a beam, identify what occurs at the point of contraflexure.

Concept The point of contraflexure (inflection) is where the curvature changes sign; equivalently, the bending moment diagram crosses zero. Final Answer Bending moment changes sign (passes through zero).

Difficulty: Easy

Shear force changes sign
Bending moment changes sign (passes through zero)
Shear force is maximum
Bending moment is maximum

Correct Answer: Bending moment changes sign (passes through zero)

Explanation:

Concept
The point of contraflexure (inflection) is where the curvature changes sign; equivalently, the bending moment diagram crosses zero.

Final Answer
Bending moment changes sign (passes through zero).

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