| A | B |
|---|
| Absolute Temperature | The lowest obtainable temperature where molecular motion stops, -400°F and -273°C. |
| Atmospheric Pressure | The weight of the atmosphere's gases pressing down on the earth. Equal to 14.696 psi at sea level and 70° F |
| Barometer | A device used to measure atmospheric pressure that is commonly calibrated in inches or millimeters of mercury. |
| Bourdon Tube | C-shaped tube manufactured of thin metal and closed on one end. When pressure is increased inside, it tends to straighten. It is used in a gage to indicate pressure. |
| British Thermal Unit | (BTU) The amount (quantity) of heat required to raise the temperature of 1lb. of water 1° F |
| Celsius | A temperature scale with 100-degree graduations between water freezing (0°C) and water boiling (100°C) |
| Conduction | Heat transfer from one molecule to another within a substance or from one substance to another. |
| Convection | Heat transfer from one place to another using a fluid |
| Fahrenheit | The temperature scale that places the boiling point of water at 212°F and the freezing point at 32°F. |
| Gram | Metric measurement term used to express weight. |
| Heat Transfer | The transfer of heat from a warmer to a colder substance. |
| Joule | Metric measurement term used to express the quantity of heat. |
| Kelvin Scale | A temperature scale where absolute 0 equals 0 or where molecular motion stops at 0. It has the same graduations per degree of change as the Celsius scale. |
| Kilopascal | A metric unit of measurement for pressure used in the air-conditioning, heating, and refrigeration field. There are 6.89 kilopascals in 1 psi. |
| Latent Heat | (Hidden heat) Heat energy absorbed or rejected when a substance is changing state and there is no change in temperature. |
| Molecular Motion | The movement of molecules within a substance |
| Molecule | The smallest particle that a substance can be broken into and still retain its chemical identity |
| Pascal | A metric unit of measurement of pressure |
| Pressure | Force per unit of area |
| Radiation | Heat passes through air, heating solid objects that in turn heat the surrounding areas. |
| Rankine Scale | The absolute Fahrenheit scale with 0 at the point where all molecular motion stops. |
| Sensible Heat | Heat that causes a change in temperature. |
| Specific Heat | The amount of heat required to raise the temperature of 1 lb. of a substance 1° F. |
| Temperature | A word used to describe the level of heat or molecular activity, expressed in Fahrenheit, Rankine, Celsius, or Kelvin units. |
| Thermometer | An instrument used to detect differences in the level of heat. |
| Vapor | The gaseous state of a substance. |
