| A | B |
|---|
| Motion | an object's change in position over time when compared with a reference point |
| Speed | the rate at which an object moves; speed depends on the distance traveled and the time taken to travel that distance |
| velocity | the speed of an object in a particular direction |
| acceleration | the rate at which velocity changes |
| force | push or pull |
| net force | the force that results from combining all the forces exerted on an object |
| friction | a force that opposes motion between two surfaces that are touching |
| gravity | a force of attraction betwen objects that is due to their masses |
| weight | a measure of the gravitional force exerted on an object |
| mass | the amount of matter that something is made of; it's value does not change with the object's location |
