| A | B |
|---|
| force | a push or pull |
| friction | a force that resists movement |
| gravitational force | attraction between any object and every other object in the universe |
| speed | how fast an object is moving |
| velocity | speed of an object in a particular direction |
| acceleration | the rate at which velocity changes |
| inertia | the tendency of an object to stay at rest unless acted upon by an outside force |
| momentum | the force needed to stop a moving object |
