| A | B |
|---|
| force | a push or pull on an object |
| free fall | an object that only has the force of gravity acting on it. |
| air resistance | the force of air on objects moving through air |
| elapsed time | the amount of time from the start of an experiment to the end of an experiment |
| Gravity | The force that pulls objects toward the earth's surface. |
| speed | Distance divided by time |
| Instantaneous speed | represented by the formula v=1/2gt |
| average speed | total distance divided by total time |
| velocity | speed with a direction |
| acceleration | the rate at wich velocity changes |
