The science of designing artificial replacements (protheses) for parts of the human body that are not working properly
The ratio of the useful work put out by a machine to the work put into that machine; efficiency is always less than 100 percent.
A machine in which work input equals work output; such as a "perfect" machine would be frictionless and 100 percent efficient.
A simple machine consisting of a bar that is free to pivot (rotate) around a fixed point (fulcrum).
A device that makes work easier by changing the size of the force applied to it and/or the direction of that force
The measure of the amount of work done in a specific amount of time; power is measured in watts and equals 1 joule/second.
A simple machine consisting of a grooved wheel with a rope or a chain running along the groove.
A simple machine consisting of a special type of inclined plane wrapped in a spiral around a cylindrical post.
A device that accomplishes work with one movement. The lever, pulley, wheel and axle, inclined plane, screw, and wedge are all simple machines.
A simple machine consisting of a moving inclined plane with one or two sloping sides; examples are knives and chisels.