| A | B |
|---|
| frame of reference | background or object used for comparison |
| motion | change in position in a certain amount of time |
| speed | rate at which an object moves |
| velocity | description of speed in a given direction |
| acceleration | rate of change in velocity |
| momentum | mass of an object times its velocity |
| negative acceleration | also known as deceleration |
| constant speed | speed that does not change |
