1. Mass:
* The most common measure of inertia. A larger mass means greater inertia. This is why a heavy object is harder to get moving or stop than a lighter object.
* Measured in kilograms (kg).
2. Moment of Inertia:
* This applies specifically to rotational motion. It describes an object's resistance to changes in its angular velocity.
* Depends on the object's mass distribution and shape. For example, a solid sphere has a smaller moment of inertia than a hollow sphere of the same mass.
* Measured in kilogram-meter squared (kg m²).
3. Rotational Inertia:
* Similar to moment of inertia, but specifically refers to the resistance to changes in angular acceleration.
* Essentially the same as moment of inertia but with a focus on the change in angular velocity over time.
* Also measured in kilogram-meter squared (kg m²).
Important Notes:
* Inertia is a fundamental property: It's not something you *measure* directly, but rather something you *observe* through its effects on an object's motion.
* Inertia doesn't change: The inertia of an object remains constant, regardless of its position, velocity, or acceleration.
* Inertia is a scalar: It has only magnitude and no direction.
Let me know if you have any other questions!
