volume (electric) charge density
121Avogadro constant — The Avogadro constant (symbols: L , N A), also called Avogadro s number, is the number of elementary entities (usually atoms or molecules) in one mole, that is (from the definition of the mole) the number of atoms in exactly 12 grams of carbon 12 …
122Poisson's equation — In mathematics, Poisson s equation is a partial differential equation with broad utility in electrostatics, mechanical engineering and theoretical physics. It is named after the French mathematician, geometer and physicist Siméon Denis Poisson.… …
123Video camera tube — In older video cameras, before the mid to late 1980s, a video camera tube or pickup tube was used instead of a charge coupled device (CCD) for converting an optical image into an electrical signal. Several types were in use from the 1930s to the… …
124Relativistic electromagnetism — is the idea of explaining electromagnetism based on relativistic (Albert Einstein 1905) arguments. It was first put forward in 1963 by Edward M. Purcell who wrote an innovative electromagnetism text in which he used special relativity to derive… …
125Mössbauer spectroscopy — A Mössbauer absorption spectrum of 57Fe Mössbauer spectroscopy is a spectroscopic technique based on the Mössbauer effect. This effect, discovered by Rudolf Mössbauer in 1957, consists in the recoil free, resonant absorption and emission of gamma …
126physical science — physical scientist. 1. any of the natural sciences dealing with inanimate matter or with energy, as physics, chemistry, and astronomy. 2. these sciences collectively. [1835 45] * * * Introduction the systematic study of the inorganic world …
127Continuum mechanics — Continuum mechanics …
128Universe — For other uses, see Universe (disambiguation). Physical cosmology …
