Products of Inertia & Principal Axes

Inside this lesson

Define the product of inertia I_xy and compute it for a composite section
Apply the symmetry shortcut: an axis of symmetry makes I_xy = 0
Find the principal-axis angle from tan(2 theta_p) = -2 I_xy/(I_x - I_y)
Compute the principal moments I_max and I_min, and link them to unsymmetric bending (M8)

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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.