what is physical significance of moment of inertia?

Moment of inertia of a point mass w.r.t. an axis of rotation is defined as the product of the mass and the square of the distance from the axis.

Moment of inertia, I = mr^{2}

Moment of inertia is the rotational analog of mass in linear motion. Moment of inertia of a rotating body offers the resistance to the rotational motion.

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