Mass
Increasing the mass of an object will increase its inertia. Also, increasing the speed at which an object is spinning will increase its rotational inertia. Additionally, increasing the distance of an object from the axis of rotation will increase its rotational inertia.
Since its length is doubled, the number of molecules present increase, resulting in an increase in mass of the rod. And we all know that mass is directly proportional to inertia, therefore the moment of inertia also increases.
This is an example of inertia, the tendency of an object in motion to stay in motion. As you increase your velocity on a skateboard, your momentum also increases, making it harder to stop because of this inertia.
The moment of inertia of the compact disk will increase by a factor of 4 (2 raised to the power of 2) when its diameter is doubled while maintaining the same thickness. This is because moment of inertia is proportional to the square of the radius.
This is an example of inertia. Inertia is the tendency of an object to resist changes in its motion. In this case, the skateboard's velocity creates momentum that makes it harder to stop suddenly.