What does the term "moment of inertia" measure?

The term "moment of inertia" specifically measures an object's resistance to rotational motion about a particular axis. This concept signifies how difficult it is to change the state of rotation of an object when a torque is applied. The moment of inertia depends on both the mass of the object and how that mass is distributed relative to the axis of rotation.

For example, a solid cylinder has a different moment of inertia compared to a hollow cylinder of the same mass and dimensions, due to the distribution of mass in relation to the axis. The greater the distance of the mass from the axis of rotation, the larger the moment of inertia, and consequently, the more torque will be necessary to change its rotational velocity.

In summary, understanding moment of inertia is essential in fields such as engineering and physics, as it plays a crucial role in analyzing the dynamics of rotating objects.