| A | B |
| motion | When an object's distance from another is changing |
| reference point | A place or object used for compariosn to determine if an object is in motion |
| International System of Units | A system of measurement based on multiples of 10 |
| meter | The basic SI unit of length |
| speed | The distance an object travels per unit of time |
| average speed | The overall rate of speed at which an object moves |
| instantaneous speed | The speed of an object at one instant of time |
| velocity | Speed in a given direction |
| slope | The steepness of a line on a graph |