| A | B |
|---|
| Lever | a bar that is free to pivot or turn around a fixed point |
| Pulley | a grooved wheel with a rope, chain, or cable running along the groove |
| wheel and axle | a simple machine consisting of a shaft or axle attached to the ceenter of a larger wheel, so that the wheel and axle rotates together |
| inclined plane | simple machine that consists of a sloping surface, such as a ramp that reduces the amount of force needed to lift something by increasing the distance over which the force is applied |
| screw | an inclined plane wrapped in a spiral around a cylindrical post |
| wedge | an inclined plane with one or two slopped sides that changes the direction of the input force |
| compound machine | two or more simple machines that operate together |
| force | push or pull |
| Work | A transfer of energy that occurs when a force makes an object move. |
| Power | the amount of work done in one second. The rate at which work is done. |
| Machine | A device that makes work easier |
| input force | the force applied to the machine |
| output force | the force applied by the machine |
| mechanical advantage | The ratio of the output force to the input force |
| efficiency | a measure of how much of the work put into the machine is changed into useful output work done by the machine. |
