| A | B |
|---|
| work | the product of force and distance when a force is used to move an object |
| joule | a unit of work equal to one newton-meter |
| machine | a device that changes the amount of force exerted or the direction in which the force is exerted |
| input force | the force exerted on a machine |
| output force | the force exerted on an object by a machine |
| mechanical advantage | the number of times the force exerted on a machine is multiplied by the machine |
| efficiency | the percentage of the input work that is converted to output work |
| actual mechanical advantage | the mechanical advantage that a machine provides in a real situation |
| ideal mechanical advantage | the mechanical advantage that a machine would have without friction |
| inclined plane | a simple machine consisting of a flat surface with one end higher than the other |
| wedge | a simple machine consisting of a device that is thick at one end and tapers to a thin edge at the other |
| screw | a simple machine that consists of an inclined plane wrapped around a central cylinder to form a spiral |
| lever | a simple machine consisting of a rigid object that pivots about a fixed point |
| fulcrum | the fixed point around which a lever pivots |
| wheel and axle | a simple machine consisting of two circular or cylindrical objects that are fastened together and rotate about a common axis |
| pulley | a simple machine consisting of a grooved wheel around which is wrapped a rope, chain, or cable |
| compound machine | a device that combines two or more simple machines |
| gears | two or more wheels linked together by interlocking teeth |
