翻訳と辞書 Words near each other ・ Specific gravity ・ Specific Gravity (album) ・ Specific identification (inventories) ・ Specific impulse ・ Specific inhalation challenge ・ Specific interval ・ Specific ion interaction theory ・ Specific kinetic energy ・ Specific language impairment ・ Specific leaf area ・ Specific legacy ・ Specific mechanical energy ・ Specific modulus ・ Specific name ・ Specific name (zoology) ・ Specific orbital energy ・ Specific output ・ Specific performance ・ Specific phobia ・ Specific physical preparedness ・ Specific potential energy ・ Specific power ・ Specific properties ・ Specific radiative intensity ・ Specific rate duty ・ Specific relative angular momentum ・ Specific Relief Act 1963 ・ Specific replant disease ・ Specific resistance ・ Specific risk 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 Specific orbital energy ： ウィキペディア英語版 Specific orbital energy In the gravitational two-body problem, the specific orbital energy $\backslash epsilon\backslash ,\backslash !$ (or vis-viva energy) of two orbiting bodies is the constant sum of their mutual potential energy ($\backslash epsilon\_p\backslash ,\backslash !$) and their total kinetic energy ($\backslash epsilon\_k\backslash ,\backslash !$), divided by the reduced mass. According to the orbital energy conservation equation (also referred to as vis-viva equation), it does not vary with time: :$\backslash epsilon\; =\; \backslash epsilon\_k+\backslash epsilon\_p\; \backslash !$ :$\backslash epsilon\; =\; \}\; =\; -\}\backslash left(1-e^2\backslash right)\; =\; -\backslash frac$ where *$v\backslash ,\backslash !$ is the relative orbital speed; *$r\backslash ,\backslash !$ is the orbital distance between the bodies; *$\backslash mu\; =\; (m\_1\; +\; m\_2)\backslash ,\backslash !$ is the sum of the standard gravitational parameters of the bodies; *$h\backslash ,\backslash !$ is the specific relative angular momentum in the sense of relative angular momentum divided by the reduced mass; *$e\backslash ,\backslash !$ is the orbital eccentricity; *$a\backslash ,\backslash !$ is the semi-major axis. It is expressed in J/kg = m2·s−2 or MJ/kg = km2·s−2. For an elliptical orbit the specific orbital energy is the negative of the additional energy required to accelerate a mass of one kilogram to escape velocity (parabolic orbit). For a hyperbolic orbit, it is equal to the excess energy compared to that of a parabolic orbit. In this case the specific orbital energy is also referred to as characteristic energy. ==Equation forms for different orbits== For an elliptical orbit, the specific orbital energy equation, when combined with conservation of specific angular momentum at one of the orbit's apsides, simplifies to: :$\backslash epsilon\; =\; -(m\_1\; +\; m\_2)\backslash ,\backslash !$ is the standard gravitational parameter; *$\backslash ,\backslash !$ is semi-major axis of the orbit. Proof: ::For an elliptical orbit with specific angular momentum ''h'' given by ::$=\; \backslash mu\; p\; =\; \backslash mu\; a\; (1-e^2)\backslash ,\backslash !$ ::we use the general form of the specific orbital energy equation, ::$\backslash epsilon=\}$ ::with the relation that the relative velocity at periapsis is ::$=\; =\; =\; =\; \backslash ,\backslash !$ ::Thus our specific orbital energy equation becomes ::$\backslash epsilon\; =\; -\; =\; =\; -\; =\; \backslash ,\backslash !$ ::and finally with the last simplification we obtain: ::$\backslash epsilon\; =\; -\}\backslash ,\backslash !.$ or the same as for an ellipse, depending on the convention for the sign of ''a''. In this case the specific orbital energy is also referred to as characteristic energy (or $C\_3\backslash ,\backslash !$) and is equal to the excess specific energy compared to that for a parabolic orbit. It is related to the hyperbolic excess velocity $v\_\; \backslash ,\backslash !$ (the orbital velocity at infinity) by :$2\backslash epsilon=C\_3=v\_^2\backslash ,\backslash !.$ It is relevant for interplanetary missions. Thus, if orbital position vector ($\backslash mathbf\backslash ,\backslash !$) and orbital velocity vector ($\backslash mathbf\backslash ,\backslash !$) are known at one position, and $\backslash mu\backslash ,\backslash !$ is known, then the energy can be computed and from that, for any other position, the orbital speed. 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「Specific orbital energy」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.