According to the different purpose of use, has been designing and manufacturing a variety of thermometers. The basis of its design are: use of solid, liquid, gas affected by temperature and thermal expansion and contraction of the phenomenon; in constant volume conditions, the gas (or steam) and pressure change due to different temperatures; the role of thermal effects; resistance varies with temperature; heat radiation and so on. In general, all physical properties of any substance as long as the temperature changes with monotonous place, a significant change in temperature can be made to mark the thermometer. |