| A | B |
|---|
| compound machine | machine that is a combination of two or more simple machines |
| efficiency | ratio of the output work done by the machine to the input work done on the machine, expressed as a percentage |
| inclined plane | simple machine that consists of a sloping surface that reduces the amount of force needed to lift something by increasing the distance over which the force is applied |
| input force | force that is applied to the machine |
| lever | simple machine consisting of a bar free to pivot about a fixed point called the fulcrum |
| machine | device that makes doing work easier by increasing the force applied to an object, changing the direction of an applied force, or increasing the distance over which a force can be applied |
| mechanical advantage | ratio of the output force exerted by a machine to the input force applied to the machine |
| output force | force applied by the machine |
| power | amount of work done, or the amount of energy transferred, divided by the time required to do the work or transfer the energy; measured in watts |
| pulley | simple machine that consists of a grooved wheel with a rope, chain, or cable running along the groove; can be either fixed or movable |
| screw | simple machine that consists of an inclined plane wrapped in a spiral around a cylindrical post |
| simple machine | machine that does work with only one movement |
| wedge | simple machine that is an inclined plane with one or two sloping sides |
| wheel and axle | simple machine that consists of a shaft or axle attached to the center of a larger wheel, so that the shaft and the wheel rotate together |
| work | transfer of energy that occurs when a force makes an object move; measured in joules |
