Angular acceleration

Radians per second squared
Unit system	SI derived unit
Unit of	Angular acceleration
Symbol	rad/s2 or rad⋅s−2

Angular acceleration is the rate of change of angular velocity. In SI units, it is measured in radians per second squared (rad/s²), and is usually denoted by the Greek letter alpha (α).

The angular acceleration can be defined as either:

where ${\displaystyle {\omega }}$ is the angular velocity, ${\displaystyle a_{T}}$ is the linear tangential acceleration, and ${\displaystyle r}$, (usually defined as the radius of the circular path of which a point moving along), is the distance from the origin of the coordinate system that defines ${\displaystyle \theta }$ and ${\displaystyle \omega }$ to the point of interest.

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