Mathematically, the degrees of freedom of a system is the number of independent parameters that define its configuration or state. In Mechanics, a train on a fixed track has one degree of freedom because its position can be defined solely by the…
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The “critical density” is the average density of matter required for the Universe to just halt its expansion, but only after an infinite amount of time. This means that the universe’s expansion would come to a halt, and not recollapse. A universe with…
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The Second Friedmann Equation describes the acceleration or deceleration of the expansion (or contraction). It describes the forces pushing or pulling on the expansion.
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“An electric charge is the property of matter where it has more or fewer electrons than protons in its atoms. Electrons carry a negative charge and protons carry a positive charge. Matter is positively charged if it contains more protons than electrons,…
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Continuum mechanics deals with the mechanical behavior of materials – modeled as a continuous mass, rather than as a set of discrete particles. One of the centers of research in continuum mechanics is at the University of Birmingham.
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Angular Momentum is the rotational analog of linear momentum. It is denoted by the lowercase omega symbol in particle physics. It may also be denoted elsewhere by the symbol as in: ; Where is mass; is velocity; and, is radius.
read moreAn index is a number or other symbol that specifies an element of an indexed family or set.
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The stress–energy tensor is a tensor physical quantity. A vector quantity is a tensor quantity that contains two components. A scalar quantity is a tensor quantity that contains only one component. These are special cases of tensors, being the simplest kind. But…
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A perfect fluid can be completely characterized by its rest frame mass density and isotropic pressure . Specifically, perfect fluids have no shear stresses, viscosity, or heat conduction. Real fluids are “sticky” and contain (and conduct) heat. Perfect fluids are idealized models…
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Dimensional analysis is the analysis of relationships between different physical quantities by identifying their base quantities and units of measure and tracking these dimensions as calculations or comparisons are performed.
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