What term describes the rate of motion in a given direction?

The correct answer is velocity, which is defined as the rate of motion in a specific direction. Velocity is a vector quantity, meaning it includes both speed (the magnitude of motion) and direction. For example, if a car is moving at 60 miles per hour to the north, its velocity would be described as 60 miles per hour north. This distinction between velocity and simple speed is crucial because speed does not provide any information about the direction of motion, whereas velocity does.

In contrast, acceleration refers to the rate of change of velocity over time, not just the motion itself or its direction. Speed simply measures how fast an object is moving, without indicating any direction. Momentum, on the other hand, is the product of an object’s mass and its velocity, describing the motion of an object but again doesn’t specifically denote the rate of motion by itself.