Area Moments of Inertia (Second Moment of Area)

Inside this lesson

Define area moment of inertia as the second moment of area, I = integral of (distance)^2 dA
State and apply the centroidal I for a rectangle, a circle, and a triangle
Explain why bending resistance scales with the cube of depth (the h-cubed intuition)
Compute the radius of gyration and recognise that I depends on the chosen axis

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Educational content covering topics typical of a first- and second-year mechanical engineering curriculum. Not a substitute for accredited coursework, and not suitable for real structural design without review by a licensed professional engineer.