| acceleration due to gravity | acceleration for any object moving under the sole influence of gravity |
| free fall | motion of objects moving freely under the force of gravity |
| projectile motion | motion of an object thrown or projected into the air |
| range | the horizontal distance traveled by a projectile |
| weight | force of gravity on an object |
| mass | amount of matter of an object |
| displacement | change in psotion |
| projectile | any object thrown into space upon which the only acting force is gravity. |
| Newton’s third law of motion | for every action (force) in nature there is an equal and opposite reaction. |
| free-body diagram | simplified representations in a problem of an object (the body), and the force vectors acting on it. |
| center of mass | a position defined relative to an object or system of objects |
| friction | a force, the resistance of motion when one object rubs against another |
| normal force | the force that surfaces exert to prevent solid objects from passing through each other |
| coefficient of sliding friction | is a number that is the ratio of the resistive force of friction (Fr) divided by the normal or perpendicular force (N) pushing the objects together. It is represented by the equation: fr = Fr/N. |
| kinetic energy | the energy an object has because of its motion. |
| gravitational potential energy | an energy that is related to gravitational force or to gravity. |
| potential energy | the stored energy within an object that exists as a result of the object's position, state, or arrangement |
| law of conservation of energy | law of conservation of energy |
| work | the energy transferred to or from an object via the application of force along a displacement |
| elastic potential energy | energy stored as a result of applying a force to deform an elastic object. |