Meyer's formula shows that the specific constant pressure heat capacity of an ideal gas is always greater than the specific constant volume heat capacity. Although both the specific constant pressure heat capacity and the specific constant volume heat capacity are functions of temperature, their difference is indeed constant.
Meyer's formula shows that although the specific heat at constant pressure and constant volume of an ideal gas varies with temperature, the difference between them is not only independent of pressure (or specific volume), but also independent of temperature. It is not only of great significance in the theory of ideal gas specific heat, but also widely used in engineering thermodynamics, gas dynamics and other disciplines.
The old translation of Meyer equation and Meyer formula. It is pointed out that at the same temperature, the specific heat at constant pressure of any ideal gas must be greater than its specific heat at constant volume, and the difference between them is always equal to a constant. It is one of the important formulas to study the thermophysical properties of ideal gas.
It was first proposed by German physicist Meyer in 1842, hence the name. According to the different units of measurement adopted by gases, there are usually the following two expressions:
Cp-cv=R, where Cp and cv are constant pressure mass specific heat and ideal gas constant volume mass specific heat respectively, and R is gas constant, and all three units are J/(kg k); (2)μcp-μcv=Rm, where ucp and μcv are the constant pressure molar specific heat and constant volume molar specific heat of ideal gas, respectively, and Rm is the universal gas constant, and the units of all three are J/(kmol k).
Meyer's formula shows that although the specific heat at constant pressure and constant volume of an ideal gas varies with temperature, the difference between them has nothing to do with not only pressure (or specific volume) but also temperature. It is not only of great significance in the theory of ideal gas specific heat, but also widely used in engineering thermodynamics, gas dynamics and other disciplines.
Meyer (German physicist)
1814165438+1was born in Heilbronn, Wü rttemberg on October 25th. He studied in the Department of Medicine of the University of Tubingen, and obtained a doctorate in medicine from 65438 to 0838. After graduation, he practiced medicine in Paris.
184 1 year, he began to study physics from medical practice. 1842, he published a paper on inorganic natural forces. Starting from the concepts of "no life, no constancy" and "cause equals effect", he expressed the thought of transformation and conservation of various forces (energy) in the process of physical chemistry.
Meyer is the first person in history to put forward the law of conservation of energy and calculate the mechanical equivalent of heat. 1845, Meyer published a paper on the relationship between organism movement and substance metabolism, which further developed his theory. 1848, Meyer published the book "Popular Celestial Mechanics" and applied his theory of thermal work to the universe.
185 1 year, Meyer published the book "Mechanical Equivalent of Heat" and summarized his work in detail. 1878 On March 20th, Meyer died of tuberculosis infection in his right arm in Haier.
Meyer put forward the concept of energy conservation from the level of general philosophy, that is, the interconnection of natural forces. Joule measured the equivalent value of thermal work from the experiment of 1843, while Helmholtz demonstrated the regularity of energy conversion from the physical theory. Therefore, the honor of putting forward the law of conservation of energy usually goes to Helmholtz, Meyer and Joule.