Angular momentum $\vec L$
The “toughness” of stopping something heavy which is spinning, or starting a spinning motion of something from rest.
$$\vec L=I\vec \omega$$
where $I$ is moment-of-inertia and $\vec \omega$ angular speed at impact. For separated objects/particles rotating, the angular momentum that each contributes with is:
$$\vec L=\vec r \times \vec p$$
where $\vec r$ is the object’s distance from the centre-of-rotation and $\vec p$ is it’s momentum.
- Vector property
- Symbol: $\vec L$
- SI-unit: Kilogram-times-metres-squared-per-second $\mathrm{kg\cdot m^2/s}$