| A | B |
| motion | a change in position of an object when compared to a reference point |
| speed | how fast an object moves from one place to another in a specific amount of time |
| average speed | the total distance traveled divided by the total time |
| velocity | the speed and direction of a moving object |
| acceleration | a change in the velocity (speed or direction) of a moving object |
| force | any push or pull that causes an object to move, or to change its speed or direction of motion |
| friction | a force that opposes motion |
| inertia | the resistance of objects to change in their motion |
| gravity | the force that tends to pull objects towards the center of the earth |
| mass | the amount of matter in an object |
| weight | a measurement of the gravitational force acting on an object |
| First Law of Motion | every object remains at rest or moves at a constant speed in a straight line unless acted upon by some outside force. |
| Second Law of Motion | the acceleration of an object is determined by the size of the force acting and the direction in which it acts |
| Third Law of Motion | for every force there is an equal and opposite force |
| momentum | an object's mass multiplied by its velocity |
| newton | the force required to cause 1 kg of mass to accelerate 1 meter per second each second |
| drag | friction between a solid surface and a liquid or gas is sometimes called this |
| air resistance | friction between a solid object and air |
| law of conservation of momentum | states that momentum can be transferred from on object to another but cannot change in total amount |