| WORDS TO KNOW |
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| DEFINITIONS |
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| Conservation of energy |
The principle that the amount of energy iin any system remains the same, even if the form of the energy changes |
| Conservation of matter |
The principle that the amount of matter in any system remains the same, even though it may have gone through physical or chemical change |
| Elastic potential energy |
Potential energy that is created by tension in an object such as a stretch rubber band |
| Energy |
The ability to do work |
| Gravitational potential energy |
Potential energy due to an object's position relative to Earth or some other gravitational field |
| Joule (J) |
The unit of energy or work |
| Kinetic energy |
Energy of a body in motion; (1/2mv2) |
| Mechanical advantage |
The ratio of output force to input force for a simple machine (resistance force/effort force or effort distance/resistance distance) |
| Potential energy |
Stored energy because of its position or tension (mgh) |
| Simple machine |
Any of the devices that work with one movement; includes the lever, wheel and axle, pulley, inclined plane, wedge, and screw |
| Work |
The transfer of energy, measured as the product of the force applied to an object and the distance moved by that object in the direction of the force applied; equal to force x distance (f x d) |
| Power |
The rate at which work is done (W/t) |
| Efficiency |
The amount of work output divided by the work input expressed as a percentage |
| Effort distance |
The distance an input force moves in a simple machine |
| Resistance distance |
The distance the output force moves the resistance |
| Watt (or kilowatt) |
The unit for power |
Biology Lab Midterm
