Question

what is moment of inertia physical meaning

Answer 1

Due  to  inertia  of    direction    the  stone  tries  to  maintain   its  direction   every   moment   this  can   be   confirmed   when  the   stone  flies   tangentially   on   release   of  the   string  

Answer 2

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.