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Informally, a physical quantity is a physical property that can be quantified. This means it can be measured and/or calculated and expressed in numbers. For example, "length" is a physical quantity that can be expressed by stating a number of some basic measurement unit such as metres or inches, while "beauty" is a property that is difficult to describe with a number. Formally, the International Vocabulary of Metrology', 3rd edition (VIM) defines quantity as: property of a phenomenon, body, or substance, where the property has a magnitude that can be expressed as a number and a reference The International Vocabulary of Metrology', 2nd ed. definied quantity as: an attribute of a phenomenon, body or substance that may be distinguished qualitatively and determined quantitatively. The value of a physical quantity Q is expressed as the product of a numerical value {Q} and a physical unit [Q].
The relationship between different physical quantities are described by quantity calculus. SI units are usually preferred today. The notion of physical dimension of a physical quantity was introduced by Fourier in 1822. From Wikipedia under the
GNU Free Documentation License  boloji.com 140px x 452px | 20.90kB [source page] here the hypothetical gravitational waves that travel faster than light should be a temporal the postulate of maximum velocity of light is saved A Temporal Physical Space And EPR Experiment A temporal physical space brings new light about experiment of Einstein Podolsky and Rosen  res.sys-con.com 100px x 100px | 3.20kB [source page] Page 1 of 2 next page Why do a physical inventory A physical inventory count is necessary to reconcile the quantity on hand stored in a database versus what is really on the shelf In a retail environment  mlit.go.jp 609px x 600px | 96.40kB [source page] miniaturized with greater value added while physical distribution tends to experience decline in cargo quantity and transport is growing smaller in lot and more frequent in shipment Fig 8 To cope with these changes in transport structure new types of transport service such as takuhaibin door to door delivery service of parcels and trunk room service are From Yahoo Image Search: "Physical quantity"  boliven.com unknown Wed, 08 Jul 2009 21:18:18 GM A . physical quantity. detector includes a pressure-responsive bridge circuit that outputs a detection voltage including a voltage component corresponding to atmospheric pressure and a voltage component corresponding to a change . quantity. ...  answersingenesis.org unknown hu, 02 Jul 2009 10:25:00 GM There can be no generally valid relationship between entropy and disorder, because entropy is a . physical quantity. which can be formulated exactly, but there is no exact formulation for disorder. The present author attempted a ...  proof-0f-dimensions.blogspot.com Samuel Reich Fri, 10 Jul 2009 02:03:00 GM Particularly in the events are different levels of . physical quantity. . The fact that there is no energy transfer during the Doppler shift means the energy duplication in going to multiple futures is reversed in Doppler time travel. ... From Google Blog Search: "Physical quantity"  news.google.com The Langar Hall Indeed, we have seen that he adopted an operational measurement=meaning principle according to which the meaningfulness of a physical quantity was ... news.google.com Alternative Information Center (AIC) When the guarantee of ethnic identity is mere quantity rather than specific qualities a psychological anxiety dictates politics. Religious Jews do not fear ... and more »  news.google.com Arab News He said the agreement also aims to promote awareness of sound eating habits, physical exercise, risk factors associated with chronic diseases like diabetes, ... and more » From Google News Search: "Physical quantity" Although length can be derived from area or volume but still length is taken as fundamental physical quantity ? Q. and not area or volume why? Asked by T N - Tue Sep 23 04:26:57 2008 - - 3 Answers - 0 Comments A. A fundamental physical quantity is one that cannot be derived from other fundamental physical quantities. Since area and volume can be derived from length, they are not fundamental. Length is NOT derived from area or volume, it is the other way around. . Answered by billrussell42 - Tue Sep 23 07:01:36 2008 Is Imaginary time the true physical quantity? Q. To describe how quantum theory shapes time and space, it is helpful to introduce the idea of imaginary time. Imaginary time sounds like something from science fiction, but it is a well-defined mathematical concept: time measured in what are called imaginary numbers. One can think of ordinary real numbers such as 1, 2, -3.5, and so on as corresponding to positions on a line stretching from left to right: zero in the middle, positive real numbers on the right, and negative real numbers on the left. Imaginary numbers can then be represented as corresponding to positions on a vertical line: zero is again in the middle, positive imaginary numbers plotted upward, and negative imaginary numbers plotted downward. Thus imaginary numbers can be… [cont.] Asked by unknown - Wed Nov 11 12:54:10 2009 - - 1 Answers - 0 Comments What are two or three other geometrical or physical quantities that are dimensionless?
Q. The quantity pi (3.14...) is a dimensionless since its a ratio of 2 lengths. Asked by Dynasty - Wed Aug 26 16:06:59 2009 - - 2 Answers - 0 Comments A. Not all scalars are dimensionless, Planck's constant is not dimensionless, for example. However, euler's constant, e is dimensionless. Both e and pi are just numbers. Angles are dimensionless. So are solid angles.Coefficient of restituion (as in collisions is dimensionless. Also, the coefficient of friction. Answered by unknown - Wed Aug 26 16:33:19 2009 From Yahoo Answer Search: "Physical quantity" |
