What is the measurement that describes the rate of change of velocity?

The rate of change of velocity is defined as acceleration. Acceleration measures how quickly an object's velocity changes over time, either in terms of increasing speed (positive acceleration), decreasing speed (negative acceleration or deceleration), or changing direction.

In mathematical terms, acceleration is expressed as the change in velocity divided by the time during which that change occurs. This relationship indicates how the velocity of an object varies, providing key insights into its motion. Therefore, when considering the description provided in the question, acceleration is the correct term that accurately encompasses this concept.

The other terms mentioned do not encapsulate the idea of a change in velocity with respect to time: speed refers to how fast an object is moving without regard to direction, force relates to the interaction that causes an object to accelerate, and momentum is a quantity defined as the product of an object's mass and its velocity. Each of these plays a distinct role in physics but does not specifically measure the rate at which velocity changes.