mechanical properties log
31Drilling fluid — This article is about fluids used when drilling a well. For fluids used with drill bits during metal working, see cutting fluid. Driller pouring a foaming agent down the rod string on a drilling rig In geotechnical engineering, drilling fluid is… …
32Helmholtz free energy — In thermodynamics, the Helmholtz free energy is a thermodynamic potential which measures the “useful” work obtainable from a closed thermodynamic system at a constant temperature and volume. For such a system, the negative of the difference in… …
33Fundamental thermodynamic relation — Thermodynamics …
34Gibbs free energy — Thermodynamics …
35Fatigue (material) — Metal fatigue redirects here. For the video game, see Metal Fatigue (disambiguation). v · d · e Materials failure modes …
36star — starless, adj. /stahr/, n., adj., v., starred, starring. n. 1. any of the heavenly bodies, except the moon, appearing as fixed luminous points in the sky at night. 2. Astron. any of the large, self luminous, heavenly bodies, as the sun, Polaris,… …
37List of unsolved problems in physics — This is a list of some of the major unsolved problems in physics. Some of these problems are theoretical, meaning that existing theories seem incapable of explaining a certain observed phenomenon or experimental result. The others are… …
38Entropy (information theory) — In information theory, entropy is a measure of the uncertainty associated with a random variable. The term by itself in this context usually refers to the Shannon entropy, which quantifies, in the sense of an expected value, the information… …
39Entropy in thermodynamics and information theory — There are close parallels between the mathematical expressions for the thermodynamic entropy, usually denoted by S , of a physical system in the statistical thermodynamics established by Ludwig Boltzmann and J. Willard Gibbs in the 1870s; and the …
40Riemann hypothesis — The real part (red) and imaginary part (blue) of the Riemann zeta function along the critical line Re(s) = 1/2. The first non trivial zeros can be seen at Im(s) = ±14.135, ±21.022 and ±25.011 …
