Question

which is the best definition of motion? motion is a change in position over time. motion is a change in speed over time. motion is a change in acceleration over time.

Explanation:

Motion in physics is defined as the change of an object's position relative to a reference point as time passes. A change in speed over time refers to acceleration, and a change in acceleration over time is jerk—neither defines motion itself.

Answer:

Motion is a change in position over time.