| 释义 |
‖ inertia|ɪˈnɜːʃɪə|
[The L., = want of art or skill, unskilfulness; inactivity, f. iners, inert-em inert. The L. term was introduced into Physics by Kepler.]
1. a. Physics. That property of matter by virtue of which it continues in its existing state, whether of rest or of uniform motion in a straight line, unless that state is altered by an external force. Originally used as L., and also called vis inertiæ (force of inertia).
centre of inertia, moment of inertia, product of inertia: see centre, moment, product.[1687Newton Principia Def. 111, Materiæ vis insita est potentia resistendi..neque differt quicquam ab inertia Massæ. 1706Phillips (ed. Kersey) Vis insita Materiæ or Vis Inertiæ, is the bare Power of Resistance only, by which every Body..endeavours to continue in that State in which it is, either of Rest or Motion.] 1713Derham Phys.-Theol. i. v. 33 The cause of the resistance of all Fluids is partly from the Friction of the parts of the Fluid, partly from the Inertia thereof. 1756Blake in Phil. Trans. LI. 2 By the principles of Mechanics, the Inertia of any bodies revolving about a Center is as the quantities of matter into the squares of the Brachia. 1803J. Wood Princ. Mech. i. 8 Inactivity may be considered..as that quality by which it resists any such change. In this..sense it is usually called the force of inactivity, the inertia, or the vis inertiæ. 1879Thomson & Tait Nat. Phil. I. i. §216 The Inertia of matter is proportional to the quantity of matter in the body. 1882Minchin Unipl. Kinemat. 107 The force of inertia of a moving particle, in any direction, is the product of its mass and its component of acceleration in that direction.
fig.1843J. Martineau Chr. Life (1867) 106 The inertia of a massive civilization. 1851Gladstone Glean. VI. xxxiv. 22 That bias..in favour of trusting to the force of inertia, to the chapter of accidents.
b. electric inertia, a term applied to the resistance offered by a circuit to sudden changes of current, due to self- or mutual induction, or both. magnetic inertia, that property of a magnetic substance which prevents its being instantaneously magnetized or demagnetized.
1886Heaviside Electr. Papers II. 60 The inertia, in the electro-magnetic case, is that of the magnetic field, not of the electricity. 1892[see induction 10].
c. Photogr. The exposure corresponding to the inertia point, from which the Hurter and Driffield speed of an emulsion may be calculated.
c1886F. Hurter in W. B. Ferguson Photogr. Res. Hurter & Driffield (1920) 12 Supposing that a source of diffuse white light of intensity one acting directly upon a plate needed a time t to so far alter a bromide of silver gelatine film on that plate that an impenetrable black deposit of silver was caused upon it on development... That time t..measures the inertia of the plate. 1888Hurter & Driffield Brit. Pat. 5545, Upon one of the fixed pair of scales..we mark what we call and hereinafter define as the ‘inertia’ or slowness of the plate. 1899C. F. Townsend Chem. for Photographers (ed. 2) iv. 73 Several of the dots are in a straight line; this is the period of correct exposure. The straight line is prolonged to meet the base line, and the number read off, which gives the ‘inertia’ of the plate. 1927C. B. Neblette Photogr. ix. 238 The inertia is an inverse measure of the speed of the plate: that is to say, a slow plate has a high inertia while a rapid plate has a low inertia. Ibid., The precise significance of the inertia as a measure of speed is somewhat difficult to define. The exposure which it represents is not the ‘threshold exposure’ (the minimum exposure necessary to produce a measurable density) nor does it indicate the maximum [? read minimum] exposure which will give proper rendering of the gradations of the subject, but an exposure somewhere between these extremes. 1955E. F. Teal tr. Lobel & Dubois's Sensitometry 96 Characteristic curves are drawn for a range of development times using a developer containing no restraining bromide. The straight line portions of the curves intersect on the log exposure axis at E, called the inertia point. Distance OE is the inertia i and the H. & D. speed is defined as 34/i, i being measured in log candle-metre-seconds.
2. transf. Inactivity; disinclination to act or exert oneself; inertness, sloth, apathy.
1822–56De Quincey Confess. (1862) 212 Tranquillity that seemed no product of inertia. 1837Carlyle Fr. Rev. I. v. ii, By wise inertia, and wise cessation of inertia, great victory has been gained. 1868M. Pattison Academ. Org. v. 148 An aimless inertia, an Oriental lassitude of habit, are not seldom seen to be the consequence of high philosophical training.
3. Special Comb.: inertia governor Engin., a governor which operates by virtue of both centrifugal force and inertia (1934 in Webster); inertia point Photogr., the point in which the straight-line portion of the characteristic curve cuts the horizontal (log exposure) axis when produced; inertia reel Motoring, a reel which enables a safety belt looped around it to be self-adjusting, esp. in inertia reel (safety) belt; also the belt served by the reel; inertia selling, the supply of goods to persons who have not requested them, in the hope that the recipients will not take the necessary action to refuse them; inertia starter Aeronaut., a starter (starter 7) which utilizes the energy stored in a flywheel.
1907Sheppard & Mees Investigations Theory Photogr. Process ii. vi. 221 The reciprocity failure may be considered to start at much the same point relatively to the *inertia points in the two plates. 1955[see sense 1 c above]. 1957K. M. Hornsby Sensitometry in Pract. ii. 9 Hurter and Driffield regarded the inertia point as a fixed characteristic of the emulsion, and they used it as a criterion by which to specify the sensitivity of emulsions. This criterion is not now recognised as an unchangeable characteristic of the emulsion since..fog will shift it to the left..and a developer containing bromide does not give a constant inertia point for all development times.
1962Daily Tel. 14 Aug. 16/6 The webbing runs off a small *inertia reel mounted at the foot of the door pillar. 1962B.S.I. News Dec. 10/1 With the exception of inertia-reel models..all the belts on display seemed to bear a Kite-mark label. 1968Economist 6 July 49/2 Not so usual are inertia reel belts, the sort that are always held at the correct tension (many injuries to wearers of seat belts may arise because they were too loose). 1970Motoring Which? Apr. 43/2 Daimler V-8 250..radio (with power operated aerial), automatic (inertia reel) safety belts; two years old. 1971Guardian 25 Jan. 7/7 Spaghetti belts are replaced by inertia reels.
1968Times 25 Apr. 14/3 Mrs. Butler..asked if the President of the Board of Trade would take powers to control *inertia selling campaigns... She deplores this exploitation of inertia sales promotion... It will be difficult for people who are subjected to inertia selling. 1970Times 13 Jan. 4/6 The Daily Mail reported on the banning..of inertia selling advertisements... Inertia selling was the practice by which companies sent unsolicited goods, then pestered people for payment if they were not returned. 1970New Statesman 13 Feb. 217/1 Now the Consumer Council is urging another dairy monopolist to abandon the practice of slipping homogenised milk, at 1d extra on to doorsteps.., and billing for it if it is accepted. The company denies that this is inertia selling, but does it matter what you call it? 1972Guardian 14 Oct. 1/4 Disreputable trading practices which victimize the housewife. Among these are ‘inertia selling’ and ‘pyramid selling’.
1929Flight 7 Mar. 181 (title) *Inertia starters for aero engines. 1931D. Garnett Grasshoppers Come 89 He..got the engine to fire with the inertia starter. 1958Times 1 July p. iv/5 Simms Motor Units Ltd. have entered a Tensec inertia starter which enables Diesel engines to be started by hand with the minimum effort. |