Final answer:
The term that defines any movement or change of position is 'motion,' making option C the correct answer. Motion is the basis of speed, velocity, and acceleration in physics, where speed is scalar and velocity is a vector quantity incorporating direction.
Step-by-step explanation:
Any movement or change of position defines motion. Therefore, the correct answer is C. Motion. In physics, motion is simply the change in position of an object over time. When we describe motion, we can consider various factors such as speed, velocity, and acceleration.
Speed is the rate at which an object covers distance. It is a scalar quantity, which means it only has magnitude and no direction. On the other hand, velocity is a vector quantity that describes the speed of an object in a specific direction. When we talk about a change in velocity, we refer to acceleration, which is the rate of change of velocity over time.
Velocity not only considers how fast an object moves (zero if it is stationary) but also the direction of its motion. Thus, an object moving 20 kilometers per hour due south has a velocity, but if we only say 20 kilometers per hour, we are referring to speed. To define momentum, we multiply the object's mass by its velocity.