Area moments — centroidal moment of inertia of a triangular section Find the second moment of area (area M.I.) of a triangle of base b and height h about an axis through its C.G. and parallel to the base. Choose the correct expression.
Mechanical Engineering
Engineering Mechanics
Difficulty: Medium
Choose an option
Answer
Correct Answer: bh3/36
Explanation
ConceptThe centroidal area moment of inertia of a triangle about a horizontal axis through the centroid (parallel to the base) is a standard result.
ResultIG, ∥base = \(\dfrac{b h^3}{36}\)
Why others are incorrectValues such as \(bh^3/12\) or \(bh^3/8\) correspond to different shapes/axes (e.g., rectangles) and are not applicable to a triangle about this specific centroidal axis.
Final Answerbh3/36