| A | B |
|---|
| reference point | an object that appears to stay in place when measuring motion |
| motion | an object's change in position relative to a reference point |
| speed | the distance traveled divided by the time interval during which the motion occured |
| average speed = total distance divided by total time | formula to calculate average speed |
| velocity | the speed of an object in a particular direction |
| acceleration | the rate at which velocity changes over time; an object accelerates if tis speed, direction, or both change |
| positive acceleration | an increase in velocity |
| negative acceleration or deceleration | a decrease in velocity |
 | graph of acceleration |
 | graph of speed |
