| 释义 |
dynamics|daɪ-, dɪˈnæmɪks|
[Plural of dynamic, after earlier names of sciences in -ics, q.v.]
1. a. The branch of Physics which treats of the action of Force: in earlier use restricted to the action of force in producing or varying motion, and thus opposed to Statics (which treats of rest or equilibrium under the action of forces); more recently (see quots. 1863–67), the name Kinetics has been introduced for the former, Dynamics being taken in a more comprehensive (and more etymological) sense, to include Statics and Kinetics. But the earlier usage, in which Statics and Dynamics are treated as co-ordinate, is still retained by some physicists, and has largely influenced the popular and transferred applications of the word and its derivatives. Also called dynamic.
1788–89Howard Royal Encycl., Dynamics is the science of moving powers; more particularly of the motion of bodies that mutually act on one another. 1804Robison Mechan. Philos. Pref., The general doctrines of Dynamics are the basis of Mechanical Philosophy. 1812–16Playfair Nat. Phil. (1819) I. 57 This part of Dynamics would lead to the consideration of Central Forces. 1829Nat. Philos., Mech. i. i. 1 (U.K.S.) In the second part, which is called dynamics, bodies are considered as submitted to the action of forces which are not in equilibrium. 1863Thomson & Tait Sketch of Elem. Dynamics 1 Dynamics is the science which investigates the action of Force..Dynamics is divided into two parts, Statics and Kinetics. 1867― Nat. Philos. Pref. 2 Keeping in view the proprieties of language, and following the example of the most logical writers, we employ the term Dynamics in its true sense as the science which treats of the action of force, whether it maintains relative rest, or produces acceleration of relative motion. The two corresponding divisions of Dynamics are thus conveniently entitled Statics and Kinetics. 1871Tyndall Fragm. Sc. (1879) I. i. 17 We deal with statics, not with dynamics.
b. That branch of any science in which force or forces are considered.
e.g. geological dynamics, that branch of geology which treats of the nature and operation of the forces by which the earth's surface has been affected, as distinguished from that which treats of the existing condition of the surface, and the order and characteristics of the strata.
1843Mill Logic vi. x. §5 (1856) II. 505 [With Comte] Social Dynamics is the theory of society considered in a state of progressive movement; while Social Statics is the theory of the consensus already spoken of as existing among the different parts of the social organism. 1845Graves Rom. Law in Encycl. Metrop. 768/1 He treats rather of the dynamics than of the statics of law—rather of those events or forces by which classes of rights begin, are modified or terminate, than of those rights and duties which accompany a given stationary legal relation. 1863Lyell Antiq. Man xv. 313 It is for those to decide who are conversant with dynamics of glacier motion.
2. transf. The moving physical or moral forces in any sphere, or the laws by which they act.
1833Chalmers Const. Man (1835) I. vi. 236 To unsettle the moral dynamics which nature hath established there. 1843J. Martineau Chr. Life (1867) 189 The great store⁓house of our spiritual dynamics. 1849Buchanan 10 Years' Confl. (1852) II. 392 Conscience seemed to be a force as little known to the dynamics of politicians in the nineteenth as in the seventeenth century. 1867Cornh. Mag. Jan. 25 No comprehensive theory of the dynamics of æsthetic evolution has yet been propounded.
3. Mus. The variation in, or amount of, volume of sound from a musical instrument or in a musical performance. Also transf.
1883in Encycl. Dict. 1908Jrnl. Folk-Song Soc. III. iii. 155 He will..find no difficulty in keeping well together with the record, as regards rhythms, twiddles, added syllables dynamics, etc. 1939A. Copland What to listen for in Music iii. 25 Merely by changing the dynamics, that is, by playing it loudly and bravely or softly and timidly, one can transform the emotional feeling of the very same succession of notes. 1942E. Blom Mus. England vii. 116 The new instrument, capable of producing not only harmony but a range of dynamics undreamt of by harpsichord players. 1962A. Nisbett Technique Sound Studio 252 Graphical representation of the envelope (or dynamics) of a single note may show separate distinctive features. |