翻訳と辞書 Words near each other ・ Inverse resolution ・ Inverse scattering problem ・ Inverse scattering transform ・ Inverse search ・ Inverse second ・ Inverse semigroup ・ Inverse square root potential ・ Inverse Symbolic Calculator ・ Inverse synthetic aperture radar ・ Inverse system ・ Inverse transform sampling ・ Inverse trigonometric functions ・ Inverse Warburg Effect ・ Inverse-chi-squared distribution ・ Inverse-gamma distribution ・ Inverse-square law ・ Inverse-variance weighting ・ Inverse-Wishart distribution ・ Invershin ・ Invershin railway station ・ Inversija ・ Inversion ・ Inversion (artwork) ・ Inversion (discrete mathematics) ・ Inversion (evolutionary biology) ・ Inversion (geology) ・ Inversion (geometry) ・ Inversion (linguistics) ・ Inversion (meteorology) ・ Inversion (music) Dictionary Lists mini英和辞書 mini和英辞書 Webster 1913 Latin-English FOLDOC Wikipedia English ウィキペディア

翻訳と辞書　辞書検索 [ 開発暫定版 ] スポンサード リンク Inverse-square law ： ウィキペディア英語版 Inverse-square law In physics, an inverse-square law is any physical law stating that a specified physical quantity or intensity is inversely proportional to the square of the distance from the source of that physical quantity. The fundamental cause for this can be understood as geometric dilution corresponding to point-source radiation into three-dimensional space (see diagram). Mathematically formulated: :$\backslash mbox\; \backslash \; \backslash propto\; \backslash \; \backslash frac\; \backslash ,$ It can also be mathematically expressed as: :$\backslash frac\; =\; \backslash frac^2\}^2\}$ The divergence of a vector field which is the resultant of radial inverse-square law fields with respect to one or more sources is everywhere proportional to the strength of the local sources, and hence zero outside sources. Newton's law of universal gravitation follows an inverse-square law, as do the effects of electric, magnetic, light, sound, and radiation phenomena. Radar energy expands during both the signal transmission and also on the reflected return, so the inverse square for both paths means that the radar will receive energy according to 1/r4 power. In order to prevent dilution of energy while propagating a signal, certain methods can be used such as a waveguide, which acts like a canal does for water, or like how a gun barrel restricts hot gas expansion to one dimension in order to prevent loss of energy transfer to a bullet. ==Justification== The inverse-square law generally applies when some force, energy, or other conserved quantity is evenly radiated outward from a point source in three-dimensional space. Since the surface area of a sphere (which is 4π''r''2 ) is proportional to the square of the radius, as the emitted radiation gets farther from the source, it is spread out over an area that is increasing in proportion to the square of the distance from the source. Hence, the intensity of radiation passing through any unit area (directly facing the point source) is inversely proportional to the square of the distance from the point source. Gauss's law applies to, and can be used with any physical quantity that acts in accord to the inverse-square relationship. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Inverse-square law」の詳細全文を読む スポンサード リンク 翻訳と辞書 : 翻訳のためのインターネットリソース Copyright(C) kotoba.ne.jp 1997-2016. All Rights Reserved.