Definition:
Temperature is the measure of the degree of thermal agitation of the molecules of a body.
Thermometry
It 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.
The measurement of the degree of thermal agitation of the molecules of a substance is not obtained directly, but in a relative way, by comparing by scales the physical behavior of the substance at which it is desired to measure the temperature with a second substance sensitive to the variations of temperature called Of thermometric substance.
Thermometer Scales
Celsius scale
It is currently set to 0 (zero) at the melting point of ice and 100 at the boiling point of the water. The interval between the two points is divided into 100 equal parts, and each part is equal to one degree Celsius.
Fahrenheit Scale
This scale was established by the German physicist Daniel Gabriel Fahrenheit in 1724.
In the Fahrenheit scale, the melting point of water is the 32nd of the scale and the boiling point at sea level is 212. The interval between these fixed points is divided into 180 equal parts and each of these parts corresponds to the variation Of a fahrenheit degree.
Kelvin scale
Based on the theory of gases, the English physicist Lord Kelvin established the absolute scale, known as kelvin scale or thermodynamics.
At the Kelvin scale, the melting point of ice corresponds to the number 273.16 and the boiling point of the water at sea level at 373. The zero of the kelvin scale is called absolute zero, at which temperature it is assumed that The molecules would be in the absence of movement, has not yet been reached in practice. Absolute zero corresponds to the temperature of -273.15 ° C.
From 1967, the unit of degree kelvin temperature (ºK) came to be called simply kelvin (K).
