List of publications on a keyword: «internal energy»

A theoretical estimate of the dependence of ultimate strength on the physical properties of a solid substance—such as density, molecular weight, melting point, and enthalpy of fusion—has been obtained. This dependence explains how these properties influence the material’s strength based on the “unpacking” concept of substance matter. The physical limits of applicability for the concept of “force” in Newtonian mechanics, and its distinction from the “unpacking” concept, are substantiated. This dependence, while similar in form to the Clapeyron-Mendeleev equation for an ideal gas, has a different physical interpretation when applied to the ultimate strength of a solid. The calculated dependence was compared with tabulated data on the ultimate strength of 15 industrial metals. This model allows for the explanation and prediction of ultimate strength values for metals in the periodic table.

We received theoretical formulas of the interconnection between melting, boiling and critical temperatures. Uniform physical representation of melting, boiling and evaporation processes was the basis for deriving the formula of interconnection between them. We use the concept of the material substance internal energy in terms of the molecules “unpacking” idea. The reference manual data on 85 substances from 13 to 855 degrees Kelvin confirms the theoretically derived formulas. We carried out the comparison of theoretical formulas and experimental data by their mean values. A simple ideal substance model with spherical molecules was considered as a model of substance molecule. The melting point is 1/3, and the boiling point ranges from 1/2 to 2/3 of the critical point for this model.