Angular velocity and acceleration from "summary" of Understanding the Laws of Motion by Kristen Petersen

Angular velocity is the rate of change in angular displacement per unit time around a fixed or defined point. Acceleration, on the other hand, is the rate of change in velocity in distance traveled per unit time.

Angular acceleration refers to an object which changes its angular velocity by turning faster at a given radius. It can also describe an object with a uniform angular velocity but moving through a different radius over a period of time.

Angular motion can be described in terms of linear motion. A circle has 360 degrees and the angular velocity of an object traveling in a circle is equal to its linear velocity divided by the radius of the circle.

Rotational motion is classified into three categories: pure rotation, rigid body rotation, and non-rigid body rotation. Pure rotation describes an object rotating around a central axis with constant angular velocity, without any linear motion.

The magnitude of angular velocity is determined by measuring how fast a particle moves relative to its center. This measurement is known as an angular displacement and it is calculated based on the angle of the line drawn from the center of the object and the current position of the object.

Rigid body rotation describes an object that is rotating around an axis, while simultaneously moving in a straight path. This type of rotation occurs when two or more forces act upon an object in such a way that the object rotates but still retains its shape.

Non-rigid body rotation describes an object that undergoes angular motion, while not maintaining its original shape. This type of rotation, unlike rigid body rotation, does not move in a straight path. A perfect example of this is a cube rolling down a hill.