| A | B |
|---|
| frame of reference | A point or set of points, assumed to be stationary, used as the “background” to describe motion. |
| magnitude | Refers to size and is expressed as a numerical value. |
| direction | The distance-independent relationship between two points in space that specifies the location of either with respect to the other. May be indicated by terms such as: north, south, positive, negative, up, or down. |
| position | Refers to where an object is relative to a frame of reference. |
| time | The duration of an action or an event. |
| scalar | A measurable quantity, such as mass, volume, and speed which are fully described by a magnitude alone. |
| distance | A scalar quantity which refers to “how much ground an object has covered” during its motion. |
| speed | A scalar quantity which refers to “how fast an object is moving.” The ratio of distance to time. |
| instantaneous speed | The speed of an object at specific moment. |
| average speed | The total distance traveled divided by the total time of travel. |
| constant speed | A speed that does not change, such as a steady speed. |
| vector | A quantity that is defined by both a magnitude and a direction together. |
| displacement | A vector quantity which refers to how far out of place an object is, or the object’s change in position. |
| velocity | A vector quantity which describes the rate at which an object changes its position. Also referred to as “speed with direction.” |
| rate | A measure of how a quantity changes with respect to time; a magnitude or frequency relative to a time unit. |
| acceleration | The rate at which an object changes its velocity, meaning there is a change in speed, direction, or both. |
