| A | B |
|---|
| speed | the rate something is moving or how fast it is going; distance traveled divided by the time interval during which the motion occurred |
| velocity | speed and direction of motion |
| force | speed and direction of motion |
| acceleration | change in velocity divided by the time interval in which the change occurred |
| force | a push or a pull associated with a change in motion |
| balanced forces | forces acting on an object that combine to produce a net force equal to zero |
| unbalanced forces | forces acting on an object that combine to produce a net nonzero force |
| friction | the resistance force of one body moving relative to another; the force between 2 objects in contact that opposes the motion of either object |
| gravity | the attraction between two particles of matter due to their mass |
| Newton's First Law of Motion | Law stating that an object at rest remains at rest and an object in motion maintains its velocity unless it experiences an unbalanced force. |
| Newton's Second Law of Motion | Law stating that the unbalanced force acting on an object equals the object’s mass times it acceleration. Force = mass times acceleration |
| Newton's Third Law of Motion | Law stating that for every action, there is an equal and object reaction (for every force, there is an equal and opposite reaction force) |
| Newton | the SI unit of force |
| free fall | the motion of a body when only the force of gravity is acting on it |
| terminal velocity | the maximum velocity reached by a falling object that occurs when the resistance of the medium is equal to the force due to gravity |
| instantaneous speed | speed at a particular instant (time) |
| average speed | the total distance traveled divided by the total time elapsed |
| scalar | quantities that are fully described by a magnitude (or numerical value) ex: speed |
| vector | quantities that are fully described by both a magnitude and a direction |
| momentum | a quantity defined as the product of an object’s mass and velocity |
