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Absolute zero temperature - the point of stopping the movement of molecules

The term "temperature" appeared at a time when physicists thought that warm bodies consist of more specific substance - heat - than the same bodies, but cold ones. And the temperature was treated as a quantity corresponding to the amount of heat in the body. Since then, the temperature of any bodies is measured in degrees. But in fact this is a measure of the kinetic energy of moving molecules, and, based on this, it should be measured in Joules, in accordance with the System of C units.

The concept of "absolute zero temperature" comes from the second law of thermodynamics. According to it, the process of heat transfer from a cold body to a hot body is impossible. This concept was introduced by the English physicist W. Thomson. To him for achievements in physics, the queen of England was granted the noble title "lord" and the title "baron of Calvin". In 1848, W. Thomson (Calvin) proposed the use of a temperature scale in which, for the initial point, an absolute zero of temperature corresponding to the extreme cold took place, and at the cost of fission took a degree of Celsius. The unit of Kelvin is 1/27316 the fraction of the temperature of the triple point of water (about 0 ° C), i.е. Temperature, at which pure water is immediately in three forms: ice, liquid water and steam. Absolute zero of temperature is the lowest possible low temperature at which the movement of molecules stops, and it is already impossible to extract heat energy from the substance. Since then, the scale of absolute temperatures has become known as his name.

The temperature is measured in different scales

The most commonly used temperature scale is called the "Celsius scale". It is built on two points: the temperature of the phase transition of water from liquid to vapor and water to ice. A. Celsius in 1742 proposed a distance between the points of reference divided by 100 intervals, and the boiling point of water taken as zero, with a freezing point of 100 degrees. But the Swede K. Linnaeus proposed to do the opposite. Since then, the water freezes at zero degrees Celsius. Although exactly Celsius, it should boil. Absolute zero for Celsius corresponds to minus 273.16 degrees Celsius.

There are several temperature scales: Fahrenheit, Reaumur, Rankin, Newton, Römer. They have different reference points and the price of division. For example, the Reaumur scale is also built on the boiling and freezing points of water, but it has 80 divisions. The Fahrenheit scale, which appeared in 1724, is used in everyday life only in some countries of the world, including the USA; Reference points: one - the temperature of the mixture of water ice - ammonia and the other - the human body. The scale is divided into one hundred divisions. Zero Celsius corresponds to 32 degrees Fahrenheit. Conversion of degrees to fahrenheit can be done using the formula: F = 1.8 C + 32. Reverse translation: C = (F - 32) / 1,8, where: F - degrees Fahrenheit, C - degrees Celsius. If you are too lazy to count, go to the online service for the transfer of Celsius to Fahrenheit. In the frame, type the number of degrees Celsius, click "Calculate", select "Fahrenheit" and click "Start". The result will appear immediately.

The Rankine scale is named after the English (or rather Scottish) physicist William J. Rankin, who was a contemporary of Kelvin and one of the founders of technical thermodynamics. In his scale, there are three important points: the beginning is absolute zero, the freezing point of water is 491.67 degrees Rankine and the boiling point of water is 671.67 degrees. The number of divisions between the freezing of water and its boiling in both Rankin and Fahrenheit is 180.

Most of these scales are used exclusively by physicists. And 40% of respondents in our days of American high school students said that they do not know what absolute zero temperature is.

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