What is the term for the rate at which velocity increases over time?

The term that describes the rate at which velocity increases over time is acceleration. Acceleration is a vector quantity, meaning it has both magnitude and direction. It represents how quickly an object's velocity changes, which can occur as an increase in speed, a decrease in speed (deceleration), or a change in direction. Mathematically, acceleration is defined as the change in velocity divided by the time over which the change occurs.

This concept is fundamental in physics as it helps explain how objects move and respond to forces. For instance, when a car speeds up, it is experiencing positive acceleration, while when it comes to a stop, it is experiencing negative acceleration.

The other terms listed refer to different concepts. Speed is the distance traveled per unit of time but does not account for direction. Momentum relates to the product of an object's mass and its velocity, providing insight into how hard it would be to stop an object in motion. Displacement refers to the change in position of an object and is a measure of the distance and direction from the starting point to the final position. Understanding acceleration is crucial for analyzing motion, impacting areas such as mechanics, vehicle dynamics, and various engineering applications.