| A | B |
| motion | an objects change in position relative to a reference point |
| acceleration | the rate at which velocity changes over time |
| speed | the distance traveled by an object divided by the time interval during which the motion occured |
| velocity | the speed of an object in a particular direction |
| force | an action exerted on a body in order to change the body's state of rest or motion |
| displacement | the change in position of an object |
| kinetic friction | the force that oposes the moveent of two surfaces that are in contact and are sliding over eah other. |
| static friction | the force that resists the initiation of sliding motion etween two surfaces that are in contact and at rest |
| net force | a single force whose external effects on a rigid body are the same as the effects of several actual forces acting on the body |
| centripetal aceleration | the acceleration directed toward the center of a circular path |
| friction | a force that opposes motion between two surfaces that are in contact. |