| A | B |
|---|
| acceleration | the rate of change in velocity |
| average speed | a rate of motion determined by dividing the total distance traveled by the total travel time |
| balanced forces | forces that are equal in size and opposite in direction |
| constant speed | speed that does not change |
| force | a push or pull one body exerts on another |
| friction | the force that opposes motion between two surfaces |
| gravity | force exerted by every object in the universe on every other object |
| inertia | the tendency of an object to resist any change in motion |
| instantaneous speed | the rate of motion at a given time |
| net force | the sum of the forces on an object when unbalanced forces are applied to it |
| speed | the rate of motion |
| velocity | the speed and direction of a moving body |
| weight | the measure of the force of gravity on an object |
