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An equation of state is a relation of state variables: $$ p=p(\rho,\,T,\,\mu,\,\alpha) $$ where $\mu$ is chemical composition and $\alpha$ the acentricity (itself dependent on $\mu$), the other variables take their normal meaning. There are some equations of state where the dependencies on these variables is non-linear (e.g., the Peng-Robinson eos), so ...


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The maximum speed of sound is the speed of light - the maximum speed at which "information" can be propagated. This will occur for an equation of state that satisfies $P = \rho c^2$, where $P$ is the pressure and $\rho$ the density. Such an incompressible equation of state may be approached in the cores of neutron stars due to the strong nuclear force ...


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Sound travels fastest in less compressible materials. But it is also affected by the state of the material, specifically its temperature. As a mechanical wave, sound must overcome the inertia of the material in which it travels. Higher temperatures mean greater kinetic energy in the molecules which carry the compression wave, and therefore less inertia ...


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The speed of sound is a function of the compressibility of materials and their density: $$c=\sqrt{\frac{E}{\rho}}$$ Where $E$ is the bulk modulus (sometimes written as $K$) and $\rho$ the density. Compressibility itself depends on the material; for instance diamond, with relatively low density (3.52 g/cm3) and very stiff covalent bonds, has a high speed of ...


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Rubber consists of many long-chain polymers. In an unstressed sample, these are randomly arranged. As a mental model think of them as anchor chains, where the angle between each link is entirely random - the overall polymer is in essence a random walk through the medium. Now, you pull on it. The net result is to better align the backbone of the polymer ...


3

Ionizing radiation loses energy in matter by creating electron-ion pairs. Suppose you have an 1 MeV charged particle stopping in a silicon crystal. The first ionization energy for free silicon atoms is about 8 eV. The ionization energy will be a little different for silicon atoms on the lattice, but not grossly so: your 1 MeV charged particle is going to ...


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According to the Review of Particle Physics (Section 33.7.4 of the 2014 edition) there are two main causes of radiation damage for electronic devices: Bulk damage due to displacement of atoms from their lattice sites. This leads to increased leakage current, carrier trapping, and build-up of space charge that changes the required operating voltage. ...


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The physical absurdity - or at least highly hyperbolic situations - of most of Roald Dahl's scenarios is the essential Dahl - it's wholesale a part of his humor and his lack compliance with physical laws is, in this respect, quite deliberate. Having said this, the "Great Big Greedy Nincompoop" disappearing up the tube is wholly possible, given the right ...


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From Wikipedia: Hardening is a metallurgical and metalworking process used to increase the hardness of a metal. The hardness of a metal is directly proportional to the uniaxial yield stress at the location of the imposed strain. A harder metal will have a higher resistance to plastic deformation than a less hard metal. Link to original ...


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Strain is not a "thing" for a material. Saying that a material "has strain" seems wrong. It's not a property of the material like volume or temperature etc. Strain is different for each process. It depends on the process or initial state. Without knowing what has happened with a material, you can only guess the strain it has experienced from looking into ...


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The glue used on plastic bottles is usually based on polyisobutylene or something similar to it. This has long hydrocarbon chains in it, and when the material is at equilibrium the polymer chains form a tangled network much like a mass of tangled wool. If you quickly stretch the polyisobutylene then the chains cannot untangle themselves because the ...


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I would assume the difference between the string and the glue is that the tendency to achieve minimum surface energy in the glue case. The glue shrinks in length so that it can decrease in surface area, while the string need not since it does not have a particular tendency for minimum surface energy.


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They are two different things. "Springyness" is called elasticity. This is described by a modulus of elasticity, also for elongation called Young's modulus $Y$. Looking at a stress-strain curve [source] as below, the elasticity is the slope of the straight line in the elastic region. If you are not familiar with a stress-strain curve, consider it as a ...



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