Degree symbol temperature is an intensive quantity and describes the energy state of matter. All materials have atoms and molecules that are in constant motion, vibrating or rotating. Simplifying this difficult subject, the more they move, the higher the temperature of the material. The temperature of an object can be defined as the average kinetic energy of its atoms and molecules, a definition of degree symbol temperature that we can understand relatively easily. Kelvin is the unit of fundamental physical magnitude called thermodynamic temperature (T) and is currently defined as the fraction 1 / 273.16 of the thermodynamic temperature of the triple point of water (exactly 0.01 ° C / 32.02 ° F).
what is hot and what is cold?
Everything is quite relative, so the terms “cold” and “hot” are not very precise or scientific. Therefore, we need a more specific way to indicate the temperature. Several different temperature scales and units have been developed in recent centuries. And since different scales have been used in various parts of the world, there are still several different scales in use. The actual specifications of some of the old temperature scales were not very exact at first (for example, the temperature of the human body), but later specific reference points and specifications were created with great accuracy.
For high temperatures there is really no limit, and it is possible to get very high. For example, the surface temperature of the sun is 5800 kelvins, while the temperature inside the sun reaches 13.6 million kelvins. But for the lower end of temperature there is a very specific limit, absolute zero being the lowest possible temperature. Absolute zero is a theoretical state that may never be achieved. Theoretically, all movement of the atoms would stop almost completely and retain only zero-point energy from the quantum mechanical system. Absolute zero in temperature equals 0 kelvins, -273.15 ° Celsius (centigrade), or -459.67 ° Fahrenheit. In outer space, the temperature is quite cold and the average of the universe is less than 3 kelvins.
International temperature scales
Thermodynamic temperature is very difficult to measure, and several international temperature scales have been published for practical measurements Still other scales have been used, for example PLTS-2000 for improved measurements of very low temperatures in the range 0.9 mK … 1 K (Provisional Low Temperature Scale of the year 2000).
By international agreement, the current ITS-90 scale is based on the aforementioned thermodynamic temperature (T). The scale defines the methods for calibrating a specified type of thermometer so that the results are accurate and repeatable throughout the world. Furthermore, the numerical values are believed to be as close as possible to the actual thermodynamic temperature (T) in time. Methods for implementing the ITS-90 temperature scale include set points and functions to interpolate temperatures between set values.
Kelvin is the base unit of temperature in the SI system (International System of Units). The abbreviation for the Kelvin unit is K (no degrees or degrees symbol). The Kelvin unit was first introduced by William Thomson (Lord Kelvin) in 1848. As mentioned above, the kelvin is currently defined as a fraction of 1 / 273.16 parts of the thermodynamic temperature of the triple point of water. ; absolute zero corresponds to 0 K. The size of a kelvin is the same as one degree Celsius. The melting temperature of ice is 273.15 K (the triple point of water is 273.16 K). Kelvin is often used in science and technology. But it’s not really used that much in everyday life. The symbol for Kelvin temperature in the scope of ITS-90 is T90 with the letter T capitalized. definition of kelvin that links it to Boltzmann’s constant, as a continuation of work to define all SI units by fundamental physical constants.
Celsius (° C)
The degree Celsius is currently a unit of temperature derived from the SI system, with the kelvin being the base unit. The abbreviation for Celsius is ° C (degree Celsius) and the magnitude of one degree symbol Celsius is the same as one kelvin. The Celsius scale and unit were first introduced by Swedish scientist Andreas Celsius in 1742. The two main reference points on the Celsius scale were the freezing point of water (or the melting point of ice), which is defined as 0 ° C, and the boiling point of water, which is 100 ° C.