What does angular velocity (ω) measure?

Angular velocity (ω) is defined as the rate at which an object rotates around a central point or axis, specifically measuring how quickly the angle changes with respect to time. It is expressed in units such as radians per second. When we say that angular velocity measures how fast the central angle changes, it refers to the increase or decrease of the angle formed between a line from the center of the circular path to the position of the moving object.

This concept is crucial in the study of rotational motion, as it provides insight into the dynamics of objects in circular paths. For example, if an object maintains a constant angular velocity, the central angle it sweeps out increases at a consistent rate, which is vital for understanding the behavior of objects in rotations, such as planets in orbits or wheels on a vehicle.

The other options do not accurately represent the definition of angular velocity. While understanding the speed of movement along a circular path or changes in radius and linear velocity are important in physics, none directly capture the essence of how fast the central angle changes, which is the core definition of angular velocity.