Discussion on IIT-JEE

In practical language , moment of inertia is a property of a body which balances it.

For eg. when u ride bicycle you don't fall because it is moment of inertia which balances the moving tyres of ur cycle.

Another eg. is  ceiling fan. when it is put on, it revolves uniformly because it is moment of inertia which balances the wings of fan.

Moment of inertia is the name given to rotational inertia, the rotational analog of mass for linear motion. It appears in the relationships for the dynamics of rotational motion. The moment of inertia must be specified with respect to a chosen axis of rotation. For a point mass the moment of inertia is just the mass times the square of perpendicular distance to the rotation axis, I = mr2. That point mass relationship becomes the basis for all other moments of inertia since any object can be built up from a collection of point masses.