It is an instrument capable of measuring the temperature of bodies.
Types of Thermometers
A) Liquid thermometer
One of the most used thermometers is mercury. Mercury is used because it can be obtained in an excellent state of purity; it is opaque in color contrasting with the glass that surrounds it, facilitating the readings, dilates or contracts uniformly as a function of temperature and presents in the liquid state a wide thermal range whose Ends are -38 ° C and + 360 ° C.
B) Pressure thermometer
This type of thermometer uses the principle of saturated steam expansion in a confined space, consisting of a bourdon tube, bellows or diaphragm, capillary tube and bulb, which undergoes variation of internal pressure as a function of temperature producing a mechanical effect in a set Of mechanical gears that will indicate the temperature values on a defined scale.
C) Thermocouple
In 1821 the German physicist Thomas Seebeck discovered that, by joining the tips of two strands of different metals (iron and copper, for example), and keeping the junctions at different temperatures, an electric current appeared through the wires.
Electronic Thermometers
The electronic thermometers base their reading systems and indicate the temperatures in the variations of some thermoelectric properties of the materials used as sensors.
These characteristic properties undergo changes as temperature changes occur in the substance to which the temperature value is desired. This change is converted through electrical signals into digital logic and indicated through displays.
Note: Temperature is the measure of the degree of thermal agitation of the molecules of a body, it does not depend on the number of molecules in motion, but on the intensity of this movement. The faster the movement of molecules "hotter" the body appears and the slower the movement of molecules, the "cooler" the body presents.
Thermometry aims to measure the degree of thermal agitation of the molecules of a given substance according to the amount of heat received or released when it undergoes a physical or chemical transformation.
