Меню Главная Случайная статья Настройки Участник:AdmiralHood/ЗРКшница Материал из https://ru.wikipedia.org Перевод единиц измерения — преобразование физической величины из одной единицы измерения в другую путём умножения на соответствующий коэффициент, связывающий единицы измерения. Содержание 1 Techniques 1.1 Process 1.2 Множители 1.3 Table ordering 2 Таблица множителей 2.1 Длина 2.2 Area 2.3 Volume 2.4 Plane angle 2.5 Solid angle 2.6 Mass 2.7 Density 2.8 Time 2.9 Frequency 2.10 Speed or velocity 2.11 Flow (volume) 2.12 Acceleration 2.13 Force 2.14 Pressure or mechanical stress 2.15 Torque or moment of force 2.16 Энергия 2.16.1 Соотношения между единицами энергии и массы, используемыми в физике 2.16.2 Прочие единицы энергии 2.17 Power or heat flow rate 2.18 Action 2.19 Dynamic viscosity 2.20 Kinematic viscosity 2.21 Electric current 2.22 Electric charge 2.23 Electric dipole 2.24 Electromotive force, electric potential difference 2.25 Electrical resistance 2.26 Capacitance 2.27 Magnetic flux 2.28 Magnetic flux density 2.29 Inductance 2.30 Temperature 2.31 Информация, энтропия 2.32 Luminous intensity 2.33 Luminance 2.34 Luminous flux 2.35 Illuminance 2.36 Radiation - source activity 2.37 Radiation - exposure 2.38 Radiation - absorbed dose 2.39 Radiation - equivalent dose 3 Software tools 3.1 General commercial sources of converters 4 See also 5 Примечания 6 Ссылки Techniques Process The process of conversion depends on the specific situation and the intended purpose. This may be governed by regulation, contract, Technical specifications or other published standards. Engineering judgment may include such factors as: The precision and accuracy of measurement and the associated uncertainty of measurement The statistical confidence interval or tolerance interval of the initial measurement The number of significant figures of the measurement The intended use of the measurement including the engineering tolerances Some conversions from one system of units to another need to be exact, without increasing or decreasing the precision of the first measurement. This is sometimes called soft conversion. It does not involve changing the physical configuration of the item being measured. By contrast, a hard conversion or an adaptive conversion may not be exactly equivalent. It changes the measurement to convenient and workable numbers and units in the new system. It sometimes involves a slightly different configuration, or size substitution, of the item. Nominal values are sometimes allowed and used. Множители Conversion between units in the metric system can be discerned by their prefixes (for example, 1 kilogram = 1000 grams, 1 milligram = 0.001 grams) and are thus not listed in this article. Exceptions are made if the unit is commonly known by another name (for example, 1 micron = 106 metre). Table ordering Within each table, the units are listed alphabetically, and the SI units (base or derived) are highlighted. Таблица множителей Ниже приведён список множителей, связывающих между собой единицы измерения различных физических величин. Для каждой физической величины приведено множество единиц измерения, многие из которых имеют лишь исторический интерес. Для каждой единицы измерения указана связь с единицами измерения системы СИ. Обозначения Символ Определение точно равно приблизительно равно цифры последовательнойсть цифр цифры повторяются бесконечно, т.е. число представляет собой бесконечну периодическую дробь, например (e.g. 8,294369 означает 8,294369369369369…) (И) представляет в основном исторический интерес Длина Длина Единица Символ Определение В системе СИ Метр (СИ) м Расстояние, которое свет в вакууме проходит за 1299792458 с[1]. 1 м ангстрем 110–10 м 0,1 нм Астрономические единицы длины астрономическая единица AU Среднее расстояние от Земли до Солнца 149597871464м [2] световой день   24 световых часа 2,59 020 683 7121013 м световой час   60 световых минут 1,0 792 528 4881012 м световая минута   60 световых секунд 1,798 754 7481010 м световая секунда   Расстоние, которое проходит свет в вакууме за 1 секунду 299792458 м световой год Расстояние, которое свет проходит за один юлианский год (365,25 сут.)[3] = 9,460 730 472 580 81015 м парсек пс Расстояние, с которого среднее расстояние от Земли до Солнца (1 астрономическая единица) имеет угловой размер в 1 угловую секунду. Или, что то же самое, расстояние, с которого звезда имеет параллакс в 1 угловую секунду при смещении наблюдателя на 1 а.е. 1 парсек = 180·60·60/ = 206264,8062... a.e. 3,085 677 821016 ± 6106 м [4] Английские единицы длины барликорн (H)   = 1/3 английского дюйма 8,4610–3 м Бор, a0 Боровский радиус атома водорода 5,2 917 720 8591011 ± 3,61020 м [5] Кабальтов (имперский)   608 английских футов 185,3184 m Кабельтов (международный)   1/10 морской мили 185,2 м Кабельтов (США)   720 английских футов = 219,456 m cubit (H)   Distance from fingers to elbow 18 in 0.5 m ell (H) ell 45 in [6] (In England usually) = 1.143 m fermi fm 11015 m[6] 11015 m finger   7/8 in = 0,022225 m finger (cloth)   4 in = 0.1143 m foot (Benot) (H) ft (Ben) 0,304799735 m foot (Clarke's; Cape) (H) ft (Cla) 0,3047972654 m фут (индийский) (И) ft Ind 0,304 799 514 m фут (международный) ft, фт. 1/3 ярда 0,3048 м 12 дюймов 0,3048 м foot (Sear's) (H) ft (Sear) 0,30479947 m foot (US Survey) ft (US) 0,304800610 m french; charriere F = 0.3 10-3 m furlong fur 10 chains = 660 ft = 220 yd [6] = 201.168 m hand   4 in [6] 0.1016 m inch (International) in 1/36 yd 1/12 ft 0.0254 m league (land) lea 3 US Statute miles [8] = 4828.032 m line ln 1/12 in [9] = 0.002116 m link (Gunter's; Surveyor's) lnk 1/100 ch [6] 0.66 ft 7.92in = 0,201168 m link (Ramsden's; Engineer's) lnk 1 ft [6] = 0.3048 m mickey   = 1,27104 m micron µ 1106 m mil; thou mil 1103 in 2,54105 m mil (Sweden and Norway) mil 10 km = 10000 m mile (geographical) (H) 6082 ft = 1853.7936 m mile (international) mi 80 chains 5280 ft 1760 yd 1609.344 m mile (tactical or data) 6000 ft 1828.8 m mile (telegraph) (H) mi 6087 ft = 1855.3176 m mile (US Survey) mi 5280 US Survey feet (5280 1609.347219 m nail (cloth)   2 in [6] = 0.057 15 m nanometer nm 1109 m 1109 m nautical league NL; nl 3 nmi [6] = 5556 m nautical mile (Admiralty) NM (Adm); nmi (Adm) = 6080 ft = 1853.184 m nautical mile (international) NM; nmi 1852 m [10] 1852 m nautical mile (US pre 1954) 1853.248 m 1853.248 m pace   2.5 ft [6] = 0.762 m palm   3 in [6] = 0.0762 m pica   12 points Dependent on point measures. point (American, English) [11][12] pt 1/72.272 in 0.000 351 450 m point (Didot; European) [12][13] pt 1/12 1/72 of pied du roi; After 1878: 5/133 cm 0.000 375 97 m; After 1878: 0.000 375 939 85 m point (PostScript) [11] pt 1/72 in = 0.000 352 7 m point (TeX) [11] pt 1/72.27 in = 0.000 351 4598 m quarter   yd = 0.2286 m rod; pole; perch (H) rd 16 ft = 5.0292 m rope (H) rope 20 ft [6] = 6.096 m span (H)   9 in [6] = 0.2286 m spat [14] 11012 m stick (H)   2 in = 0.0508 m stigma; bicron (picometre) pm 11012 m twip twp 1/1440 in = 1.7638105 m x unit; siegbahn xu 1.00211013 m [6] Английские единицы длины дюйм   1/12 фута 2,54 см фут   12 дюймов 30,48 см ярд   3 фута = 36 дюймов 91,44 см фэтом fm 1,8288 m Чейн (Gunter's; Surveyor's) ch 66 футов[8] 20,11 684 m миля   1760 ярдов = 5280 футов 1,609344 км Старые русские единицы длины (с 1835 года) точка   1/100 дюйма = 1/10 линии 0,254 мм линия   1/10 дюйма 2,54 мм дюйм   1/12 фута 2,54 см вершок   1,75 дюйма = 1/4 пяди = 1/16 аршина 4,445 см пядь   7 дюймов = 1/4 аршина 17,78 см фут   12 дюймов = 1 английский фут 30,48 см аршин   28 дюймов = 4 пяди = 16 вершков 71,12 см ярд   3 фута = 36 дюймов 91,44 см казённая сажень   7 футов = 3 аршина = 48 вершков 2,1336 м шест   10 казённых саженей 21,336 м цепь   50 казённых саженей 106,68 м путевая верста   500 казённых саженей 1,0668 км английская миля   1760 ярдов = 5280 футов 1,609344 км межевая верста   1000 казённых саженей 2,1336 км географическая миля   7 путевых вёрст 7,4676 км Area Area Name of unit Symbol Definition Relation to SI units acre (international) ac 1 ch 10 ch = 4840 sq yd 4 046.856 4224 m2 acre (U. S. survey) ac 10 sq ch = 4840 sq yd, also 43560 sq ft. 4 046.873 m2 [15] are a 100 m2 = 100 m2 barn b 1028 m2 = 1028 m2 barony   4000 ac 1.618 742107 m2 board bd 1 in 1 ft = 7.741 92103 m2 boiler horsepower equivalent direct radiation bhp EDR (1 ft2) (1 bhp) / (240 BTUIT/h) 12.958 174 m2 circular inch circ in /4 sq in 5.067 075104 m2 circular mil; circular thou circ mil /4 mil2 5.067 0751010 m2 cord   192 bd = 1.486 448 64 m2 dunam   1 000 m2 = 1 000 m2 guntha   121 sq yd 101.17 m2 hectare ha 10 000 m2 10 000 m2 hide   120 ac (variable) 5105 m2 rood ro ac = 1 011.714 1056 m2 section 1 mi 1 mi = 2.589 988 110 336106 m2 shed   1052 m2 = 1052 m2 square (roofing) 10 ft 10 ft = 9.290 304 m2 square chain (international) sq ch 66 ft 66 ft = 1/10 ac 404.685 642 24 m2 square chain (US Survey) sq ch 66 ft(US) 66 ft(US) = 1/10 ac 404.687 3 m2 square foot sq ft 1 ft 1 ft 9.290 304102 m2 square foot (US Survey) sq ft 1 ft (US) 1 ft (US) 9.290 341 161 327 4910-2 m2 square inch sq in 1 in 1 in 6.4516104 m2 square kilometre km2 1 km 1 km = 106 m2 square link (Gunter's)(International) sq lnk 1 lnk 1 lnk 0.66 ft 0.66 ft = 4.046 856 4224102 m2 square link (Gunter's)(US Survey) sq lnk 1 lnk 1 lnk 0.66 ft(US) 0.66 ft(US) 4.046 872102 m2 square link (Ramsden's) sq lnk 1 lnk 1 lnk 1 ft 1 ft = 0.09290304 m2 square metre (SI unit) m2 1 m 1 m = 1 m2 square mil; square thou sq mil 1 mil 1 mil = 6.45161010 m2 square mile sq mi 1 mi 1 mi = 2.589 988 110 336106 m2 square mile (US Survey) sq mi 1 mi (US) 1 mi (US) 2.589 998 47106 m2 square rod/pole/perch sq rd 1 rd 1 rd = 25.292 852 64 m2 square yard (International) sq yd 1 yd 1 yd 0.836 127 36 m2 stremma   1 000 m2 = 1 000 m2 township   36 sq mi (US) 9.323 994107 m2 yardland   30 ac 1.2105 m2 Volume Volume Name of unit Symbol Definition Relation to SI units acre-foot ac ft 1 ac x 1 ft = 43 560 ft3 = 1 233.481 837 547 52 m3 acre-inch   1 ac 1 in = 102.790 153 128 96 m3 barrel (imperial) bl (imp) 36 gal (imp) = 0.163 659 24 m3 barrel (petroleum) bl; bbl 42 gal (US) = 0.158 987 294 928 m3 barrel (US dry) bl (US) 105 qt (US) = 105/32 bu (US lvl) = 0.115 628 198 985 075 m3 barrel (US fluid) fl bl (US) 31 gal (US) = 0.119 240 471 196 m3 board-foot fbm 144 cu in 2.359 737 216103 m3 bucket (imperial) bkt 4 gal (imp) = 0.018 184 36 m3 bushel (imperial) bu (imp) 8 gal (imp) = 0.036 368 72 m3 bushel (US dry heaped) bu (US) 1 bu (US lvl) = 0.044 048 837 7086 m3 bushel (US dry level) bu (US lvl) 2 150.42 cu in = 0.035 239 070 166 88 m3 butt, pipe   126 gal (wine) = 0.476 961 884 784 m3 coomb   4 bu (imp) = 0.145 474 88 m3 cord (firewood)   8 ft 4 ft 4 ft = 3.624 556 363 776 m3 cord-foot   16 cu ft = 0.453 069 545 472 m3 cubic fathom cu fm 1 fm 1 fm 1 fm = 6.116 438 863 872 m3 cubic foot cu ft 1 ft 1 ft 1 ft 0.028 316 846 592 m3 cubic inch cu in 1 in 1 in 1 in 16.387 064106 m3 cubic metre (SI unit) m3 1 m 1 m 1 m 1 m3 cubic mile cu mi 1 mi 1 mi 1 mi 4 168 181 825.440 579 584 m3 cubic yard cu yd 27 cu ft 0.764 554 857 984 m3 cup (breakfast)   10 fl oz (imp) = 284.130 625106 m3 cup (Canadian) c (CA) 8 fl oz (imp) = 227.3045106 m3 cup (metric) c 250.0106 m3 = 250.0106 m3 cup (US customary) c (US) 8 US fl oz 1/16 gal (US) = 236.588 2365106 m3 cup (US food nutrition labeling) c (US) 240 mL[16] = 2,4104 m3 dash (imperial)   1/384 gi (imp) = pinch (imp) = 369.961 751 302 08 3109 m3 dash (US)   1/96 US fl oz = US pinch = 308.057 599 609 375109 m3 dessertspoon (imperial)   1/12 gi (imp) = 11.838 776 0416106 m3 drop (imperial) gtt 1/288 fl oz (imp) = 98.656 467 013 8109 m3 drop (imperial) (alt) gtt 1/1 824 gi (imp) 77.886 684109 m3 drop (medical)   1/12 ml = 83.03109 m3 drop (metric)   1/20 mL = 50.0109 m3 drop (US) gtt 1/360 US fl oz = 82.148 693 22916109 m3 drop (US) (alt) gtt 1/456 US fl oz 64.854 231109 m3 fifth   1/5 US gal = 757.082 3568106 m3 firkin   9 gal (US) = 0.034 068 706 056 m3 fluid drachm (imperial) fl dr fl oz (imp) = 3.551 632 8125106 m3 fluid dram (US); US fluidram fl dr US fl oz = 3.696 691 195 3125106 m3 fluid scruple (imperial) fl s 1/24 fl oz (imp) = 1.183 877 60416106 m3 gallon (beer) beer gal 282 cu in = 4.621 152 048103 m3 gallon (imperial) gal (imp) 4.546 09 L 4.546 09103 m3 gallon (US dry) gal (US) bu (US lvl) = 4.404 883 770 86103 m3 gallon (US fluid; Wine) gal (US) 231 cu in 3.785 411 784103 m3 gill (imperial); Noggin gi (imp); nog 5 fl oz (imp) = 142.065 3125106 m3 gill (US) gi (US) 4 US fl oz = 118.294 118 25106 m3 hogshead (imperial) hhd (imp) 2 bl (imp) = 0.327 318 48 m3 hogshead (US) hhd (US) 2 fl bl (US) = 0.238 480 942 392 m3 jigger (bartending)   1 US fl oz 44.36106 m3 kilderkin   18 gal (imp) = 0.081 829 62 m3 lambda 1 mm3 = 1109 m3 last   80 bu (imp) = 2.909 4976 m3 litre L 1 dm3 [17] 0.001 m3 load   50 cu ft = 1.415 842 3296 m3 minim (imperial) min 1/480 fl oz (imp) = 1/60 fl dr (imp) = 59.193 880 208 3109 m3 minim (US) min 1/480 US fl oz = 1/60 US fl dr = 61.611 519 921 875109 m3 ounce (fluid imperial) fl oz (imp) 1/160 gal (imp) 28.413 0625106 m3 ounce (fluid US customary) US fl oz 1/128 gal (US) 29.573 529 5625106 m3 ounce (fluid US food nutrition labeling) US fl oz 30 mL[16] 3105 m3 peck (imperial) pk 2 gal (imp) = 9.092 18103 m3 peck (US dry) pk US lvl bu = 8.809 767 541 72103 m3 perch per 16 ft 1 ft 1 ft = 0.700 841 953 152 m3 pinch (imperial)   1/192 gi (imp) = tsp (imp) = 739.923 502 60416109 m3 pinch (US)   1/48 US fl oz = US tsp = 616.115 199 218 75109 m3 pint (imperial) pt (imp) gal (imp) = 568.261 25106 m3 pint (US dry) pt (US dry) 1/64 bu (US lvl) gal (US dry) = 550.610 471 3575106 m3 pint (US fluid) pt (US fl) gal (US) = 473.176 473106 m3 pony   3/4 US fl oz = 22.180 147 171 875106 m3[Converter 1] pottle; quartern   gal (imp) = 80 fl oz (imp) = 2.273 045103 m3 quart (imperial) qt (imp) gal (imp) = 1.136 5225103 m3 quart (US dry) qt (US) 1/32 bu (US lvl) = gal (US dry) = 1.101 220 942 715103 m3 quart (US fluid) qt (US) gal (US fl) = 946.352 946106 m3 quarter; pail   8 bu (imp) = 0.290 949 76 m3 register ton   100 cu ft = 2.831 684 6592 m3 sack (imperial); bag   3 bu (imp) = 0.109 106 16 m3Ошибка: некорректно задана дата установки (исправьте через подстановку шаблона) sack (US)   3 bu (US lvl) = 0.105 717 210 500 64 m3 seam   8 bu (US lvl) = 0.281 912 561 335 04 m3 shot   1 US fl oz 29.57106 m3 strike (imperial)   2 bu (imp) = 0.072 737 44 m3 strike (US)   2 bu (US lvl) = 0.070 478 140 333 76 m3 tablespoon (Australian metric)   20.0106 m3 tablespoon (Canadian) tbsp fl oz (imp) = 14.206 531 25106 m3 tablespoon (imperial) tbsp 5/8 fl oz (imp) = 17.758 164 0625106 m3 tablespoon (metric)   15.0106 m3 tablespoon (US customary) tbsp US fl oz = 14.786 764 7825106 m3 tablespoon (US food nutrition labeling) tbsp 15 mL[16] = 1,5105 m3 teaspoon (Canadian) tsp 1/6 fl oz (imp) = 4.735 510 416106 m3 teaspoon (imperial) tsp 1/24 gi (imp) = 5.919 388 02083106 m3 teaspoon (metric)   5.0106 m3 = 5.0106 m3 teaspoon (US customary) tsp 1/6 US fl oz = 4.928 921 595106 m3 teaspoon (US food nutrition labeling) tsp 5 mL[16] = 5106 m3 timber foot   1 cu ft = 0.028 316 846 592 m3 ton (displacement)   35 cu ft = 0.991 089 630 72 m3 ton (freight)   40 cu ft = 1.132 673 863 68 m3 ton (water)   28 bu (imp) = 1.018 324 16 m3 tun   252 gal (wine) = 0.953 923 769 568 m3 wey (US)   40 bu (US lvl) = 1.409 562 806 6752 m3 Plane angle Plane angle Name of unit Symbol Definition Relation to SI units angular mil µ 2/6400 rad 0.981 74810-3 rad arcminute; MOA ' 1°/60 0.290 88810-3 rad arcsecond " 1°/3600 4.848 13710-6 rad centesimal minute of arc ' 1 grad/100 0.157 08010-3 rad centesimal second of arc " 1 grad/(10 000) 1.570 79610-6 rad degree (of arc) ° 1/360 of a revolution /180 rad 17.453 29310-3 rad grad; gradian; gon grad 1/400 of a revolution 2/400 rad 0.9° 15.707 96310-3 rad octant   45° 0.785 398 rad quadrant   90° 1.570 796 rad radian (SI unit) rad The angle subtended at the center of a circle by an arc whose length is equal to the circle's radius. One full revolution encompasses 2 radians. = 1 rad sextant   60° 1.047 198 rad sign   30° 0.523 599 rad Solid angle Solid angle Name of unit Symbol Definition Relation to SI units steradian (SI unit) sr The solid angle subtended at the center of a sphere of radius r by a portion of the surface of the sphere having an area r2. A sphere encompasses 4 sr.[14] = 1 sr Mass Notes: See Weight for detail of mass/weight distinction and conversion. In this table, the unit gee is used to denote standard gravity in order to avoid confusion with the "g" symbol for grams. In physics, the pound of mass is sometimes written lbm to distinguish it from the pound-force (lbf). It should not be read as the mongrel unit "pound metre". Mass Name of unit Symbol Definition Relation to SI units Атомная единица массы АЕМ, у.е. 1,660 538 731027 ± 1,31036 кг Масса электрона me 9,109 382 151031 ± 451039 кг [18] bag (coffee)   60 kg = 60 kg bag (Portland cement)   94 lb av = 42.637 682 78 kg barge   22 sh tn = 20 411.656 65 kg Карат карат 3 1/6 gr 205.196 548 333 mg carat (metric) ct 200 mg = 200 mg clove   8 lb av = 3.628 738 96 kg crith   89.9349 mg Дальтон Da 1,660 902 101027 ± 1,31036 кг dram (apothecary; troy) dr t 60 gr = 3.887 9346 g dram (avoirdupois) dr av 27 11/32 gr = 1.771 845 195 3125 g electronvolt eV 1 eV (energy unit) / c2 = 1.782610-36 kg gamma 1 g = 1 g grain gr 1/7000 lb av 64.798 91 mg grave G grave was the original name of the kilogram 1 kg hundredweight (long) long cwt or cwt 112 lb av = 50.802 345 44 kg hundredweight (short); cental sh cwt 100 lb av = 45.359 237 kg kilogram kg mass of the prototype near Paris ( mass of 1L of water) 1 kg (SI base unit)[1] kip kip 1000 lb av = 453.592 37 kg mark   8 oz t = 248.827 8144 g mite   1/20 gr = 3.239 9455 mg mite (metric)   1/20 g = 50 mg ounce (apothecary; troy) oz t 1/12 lb t = 31.103 4768 g ounce (avoirdupois) oz av 1/16 lb = 28.349 523 125 g ounce (US food nutrition labeling) oz 28 g[16] = 28 g pennyweight dwt; pwt 1/20 oz t = 1.555 173 84 g point   1/100 ct = 2 mg pound lb slug·ft/s2 = 0.45359237 kg pound (avoirdupois) lb av 0.453 592 37 kg = 7000 grains 0.453 592 37 kg pound (metric)   500 g = 500 g pound (troy) lb t 5 760 grains = 0.373 241 7216 kg quarter (imperial)   1/4 long cwt = 2 st = 28 lb av = 12.700 586 36 kg quarter (informal)   short tn = 226.796 185 kg quarter, long (informal)   long tn = 254.011 7272 kg quintal (metric) q 100 kg = 100 kg scruple (apothecary) s ap 20 gr = 1.295 9782 g sheet   1/700 lb av = 647.9891 mg slug; geepound; hyl slug 1 gee 1 lb av 1 s2/ft 14.593 903 kg stone st 14 lb av = 6.350 293 18 kg ton, assay (long) AT 1 mg 1 long tn 1 oz t 32.666 667 g ton, assay (short) AT 1 mg 1 sh tn 1 oz t 29.166 667 g ton, long long tn or ton 2 240 lb = 1 016.046 9088 kg ton, short sh tn 2 000 lb = 907.184 74 kg tonne (mts unit) t 1 000 kg = 1 000 kg wey   252 lb = 18 st = 114.305 277 24 kg (variants exist) Zentner Ztr. Definitions vary; see [19] and.[14] Density Density Name of unit Symbol Definition Relation to SI units gram per millilitre g/mL g/mL = 1000 kg/m3 kilogram per cubic metre (SI unit) kg/m3 kg/m3 = 1 kg/m3 kilogram per litre kg/L kg/L = 1000 kg/m3 ounce (avoirdupois) per cubic foot oz/ft3 oz/ft3 1,001153961 kg/m3 ounce (avoirdupois) per cubic inch oz/in3 oz/in3 1,729994044103 kg/m3 ounce (avoirdupois) per gallon (imperial) oz/gal oz/gal 6,236023291 kg/m3 ounce (avoirdupois) per gallon (US fluid) oz/gal oz/gal 7,489151707 kg/m3 pound (avoirdupois) per cubic foot lb/ft3 lb/ft3 16,01846337 kg/m3 pound (avoirdupois) per cubic inch lb/in3 lb/in3 2,767990471104 kg/m3 pound (avoirdupois) per gallon (imperial) lb/gal lb/gal 99,77637266 kg/m3 pound (avoirdupois) per gallon (US fluid) lb/gal lb/gal 119,8264273 kg/m3 slug per cubic foot slug/ft3 slug/ft3 515,3788184 kg/m3 Time Time, t Name of unit Symbol Definition Relation to SI units atomic unit of time au a0/(·c) 2.418 884 2541017 s Callippic cycle   441 mo (hollow) + 499 mo (full) = 76 a of 365.25 d = 2.398 3776109 s century c 100 a (see below for definition of year length) = 100 years day d = 24 h = 1440 min = 86400 s day (sidereal) d Time needed for the Earth to rotate once around its axis, determined from successive transits of a very distant astronomical object across an observer's meridian (International Celestial Reference Frame) 86 164.1 s decade dec 10 a (see below for definition of year length) = 10 years fortnight fn 2 wk = 1 209 600 s helek 1/1 080 h = 3.3 s Hipparchic cycle   4 Callippic cycles - 1 d = 9.593 424109 s hour h 60 min = 3 600 s jiffy j 1/60 s = .016 s jiffy (alternate) ja 1/100 s = 10 ms ke (quarter of an hour)   h = 1/96 d = 60 60 / 4 s = 900 s = 60 / 4 min = 15 min ke (traditional)   1/100 d = 24 60 60 / 100 s = 864 s = 24 * 60 / 100 min = 14.4 min lustre; lustrum   5 a of 365 d = 1.5768108 s Metonic cycle; enneadecaeteris   110 mo (hollow) + 125 mo (full) = 6940 d 19 a = 5.996 16108 s millennium   1 000 a (see below for definition of year length) = 1000 years milliday md 1/1 000 d = 24 60 60 / 1 000 s = 86.4 s minute min 60 s, due to leap seconds sometimes 59 s or 61 s, = 60 s moment   90 s = 90 s month (full) mo 30 d[20] = 2 592 000 s month (Greg. av.) mo Average Gregorian month = 365.2425/12 d = 30.436875 d 2.6297106 s month (hollow) mo 29 d[20] = 2 505 600 s month (synodic) mo Cycle time of moon phases 29.530589 days (Average) 2.551106 s octaeteris   = 48 mo (full) + 48 mo (hollow) + 3 mo (full)[21][22] = 8 a of 365.25 d = 2922 d = 2.524 608108 s Planck time   (G/c5) 1.351 211 8681043 s second s time of 9 192 631 770 periods of the radiation corresponding to the transition between the 2 hyperfine levels of the ground state of the caesium 133 atom at 0 K[1] (but other seconds are sometimes used in astronomy) (SI base unit) shake   108 s = 10 ns sigma   106 s = 1 s Sothic cycle   1 461 a of 365 d = 4.607 40961010 s svedberg S 1013 s = 100 fs week wk 7 d = 168 h = 10 080 min = 604 800 s year (Gregorian) a, y, or yr = 365.2425 d average, calculated from common years (365 d) plus leap years (366 d) on most years divisible by 4. See leap year for details. = 31 556 952 s year (Julian) a, y, or yr = 365.25 d average, calculated from common years (365 d) plus one leap year (366 d) every four years = 31 557 600 s year (sidereal) a, y, or yr time taken for Sun to return to the same position with respect to the stars of the celestial sphere 365.256 363 d 31 558 149.7632 s year (tropical) a, y, or yr Length of time it takes for the Sun to return to the same position in the cycle of seasons 365.242 190 d 31 556 925 s Where UTC is observed, the length of time units longer than 1 s may increase or decrease by 1 s if a leap second occurs during the time interval of interest. Frequency Frequency Name of unit Symbol Definition Relation to SI units hertz (SI unit) Hz Number of cycles per second = 1 Hz = 1/s revolutions per minute rpm One unit rpm equals one rotation completed around a fixed axis in one minute of time. 0,104719755 rad/s Speed or velocity Speed Name of unit Symbol Definition Relation to SI units foot per hour fph 1 ft/h 8.466 667105 m/s foot per minute fpm 1 ft/min = 5.08103 m/s foot per second fps 1 ft/s = 3.048101 m/s furlong per fortnight   furlong/fortnight 1.663 095104 m/s inch per hour iph 1 in/hr 7.05 556106 m/s inch per minute ipm 1 in/min 4.23 333104 m/s inch per second ips 1 in/s = 2.54102 m/s kilometre per hour km/h 1 km/h 2.777 778101 m/s knot kn, kt 1 NM/h = 1.852 km/h 0.514 444 m/s knot (Admiralty) kn 1 NM (Adm)/h = 1.853 184 km/h = 0.514 773 m/s mach number M Ratio of the speed to the speed of sound in the medium. Varies especially with temperature. About 1225 km/h (761 mph) in air at sea level to about 1062 km/h (660 mph) at jet altitudes. Unitless 340 to 295 m/s for aircraft metre per second (SI unit) m/s 1 m/s = 1 m/s mile per hour mph 1 mi/h = 0.447 04 m/s mile per minute mpm 1 mi/min = 26.8224 m/s mile per second mps 1 mi/s = 1 609.344 m/s speed of light in vacuum c 299 792 458 m/s = 299 792 458 m/s speed of sound in air s Varies especially with temperature. About 1225 km/h (761 mph) in air at sea level to about 1062 km/h (660 mph) at jet altitudes. 340 to 295 m/s at aircraft altitudes A velocity consists of a speed combined with a direction; the speed part of the velocity takes units of speed. Flow (volume) Flow Name of unit Symbol Definition Relation to SI units cubic foot per minute CFM 1 ft3/min = 4,719474432104 m3/s cubic foot per second ft3/s 1 ft3/s = 0,028316846592 m3/s cubic inch per minute in3/min 1 in3/min = 2,731177310-7 m3/s cubic inch per second in3/s 1 in3/s = 1,6387064105 m3/s cubic metre per second (SI unit) m3/s 1 m3/s = 1 m3/s gallon (US fluid) per day GPD 1 gal/d = 4,38126363810-8 m3/s gallon (US fluid) per hour GPH 1 gal/h = 1,05150327310-6 m3/s gallon (US fluid) per minute GPM 1 gal/min = 6,30901964105 m3/s litre per minute LPM 1 L/min = 1.610-5 m3/s Acceleration Acceleration Name of unit Symbol Definition Relation to SI units foot per hour per second fph/s 1 ft/(h·s) 8.466 667105 m/s2 foot per minute per second fpm/s 1 ft/(min·s) = 5.08103 m/s2 foot per second squared fps2 1 ft/s2 = 3.048101 m/s2 gal; galileo Gal 1 cm/s2 = 102 m/s2 inch per minute per second ipm/s 1 in/(min·s) 4.233 333104 m/s2 inch per second squared ips2 1 in/s2 = 2.54102 m/s2 knot per second kn/s 1 kn/s 5.144 444101 m/s2 metre per second squared (SI unit) m/s2 1 m/s2 = 1 m/s2 mile per hour per second mph/s 1 mi/(h·s) = 4.4704101 m/s2 mile per minute per second mpm/s 1 mi/(min·s) = 26.8224 m/s2 mile per second squared mps2 1 mi/s2 = 1.609 344103 m/s2 standard gravity g 9.806 65 m/s2 = 9.806 65 m/s2 Force Force Name of unit Symbol Definition Relation to SI units atomic unit of force me·2·c2/a0 8.238 722 06108 N [23] dyne (cgs unit) dyn g·cm/s2 = 105 N kilogram-force; kilopond; grave-force kgf; kp; Gf g 1 kg = 9.806 65 N kip; kip-force kip; kipf; klbf g 1 000 lb = 4.448 221 615 2605103 N milligrave-force, gravet-force mGf; gf g 1 g = 9.806 65 mN newton (SI unit) N A force capable of giving a mass of one kg an acceleration of one metre per second, per second.[24] = 1 N = 1 kg·m/s2 ounce-force ozf g 1 oz = 0.278 013 850 953 7812 N pound-force lbf g 1 lb = 4.448 221 615 2605 N poundal pdl 1 lb·ft/s2 = 0.138 254 954 376 N sthene (mts unit) sn 1 t·m/s2 = 1103 N ton-force tnf g 1 sh tn = 8.896 443 230 521103 N See also: Conversion between weight (force) and mass Pressure or mechanical stress Pressure Name of unit Symbol Definition Relation to SI units Атмосфера (физическая) атм 760 мм рт. ст. 101 325 Па [25] Атмосфера (техническая) at 1 кГ/см2 = 9,806 65104 Па [25] Бар бар 105 Па barye (cgs unit)   1 dyn/cm2 = 0,1 Pa мм рт. ст. 13 595,1 kg/m3 1 cm g 1.333 22103 Pa [25] сантиметр водного столба (4 °C) 999,972 kg/m3 1 cm g 98,063 8 Pa [25] foot of mercury (conventional) ftHg 13 595.1 kg/m3 1 ft g 40.636 66103 Pa [25] foot of water (39.2 °F) ftH2O 999.972 kg/m3 1 ft g 2.988 98103 Pa [25] inch of mercury (conventional) inHg 13 595.1 kg/m3 1 in g 3.386 389103 Pa [25] inch of water (39.2 °F) inH2O 999.972 kg/m3 1 in g 249.082 Pa [25] kilogram-force per square millimetre kgf/mm2 1 kgf/mm2 = 9.806 65106 Pa [25] kip per square inch ksi 1 kipf/sq in 6.894 757106 Pa [25] micron (micrometre) of mercury ${\displaystyle \mu }$mHg 13 595.1 kg/m3 1 ${\displaystyle \mu }$m g 0.001 torr 0.133 322 4 Pa [25] millimetre of mercury mmHg 13 595.1 kg/m3 1 mm g 1 torr 133.3224 Pa [25] millimetre of water (3.98 °C) mmH2O 999.972 kg/m3 1 mm g = 0.999 972 kgf/m2 = 9.806 38 Pa pascal (SI unit) Pa N/m2 = kg/(m·s2) = 1 Pa [26] pize (mts unit) pz 1 000 kg/m·s2 = 1103 Pa = 1 kPa pound per square foot psf 1 lbf/ft2 47.880 26 Pa [25] pound per square inch psi 1 lbf/in2 6.894 757103 Pa [25] poundal per square foot pdl/sq ft 1 pdl/sq ft 1.488 164 Pa [25] short ton per square foot   1 sh tn g / 1 sq ft 95.760 518103 Pa torr torr 101 325/760 Pa 133.322 4 Pa [25] Torque or moment of force Torque Name of unit Symbol Definition Relation to SI units foot-pound force ft lbf g 1 lb 1 ft = 1.355 817 948 331 4004 N·m foot-poundal ft pdl 1 lb·ft2/s2 = 4.214 011 009 380 48102 N·m inch-pound force in lbf g 1 lb 1 in = 0.112 984 829 027 6167 N·m metre kilogram m kg N m / g 0.101 971 621 N·m Newton metre (SI unit) N·m N m = kg·m2/s2 = 1 N·m Энергия Вычислено исходя из следующих фундаментальных констант[27]: 1 кг/а.е.м. = 103 NA, где NA = 6,022 141 29(27)1026 моль–1 — число Авогадро. 1 кг/Дж = с2, где с = 299 792 458 м/с — скорость света в вакууме (точное значение). 1 МэВ/Дж = 106 e, где e = 1,602 176 565(35)10–19 Кл — заряд электрона. Единица кг а.е.м. Дж МэВ 1 кг 1 6,022 141 29(27)1026 8,987 551 787(1)1016 5,609 588 84(12)1029 1 а.е.м. 1,660 538 921(74)10–27 1 1,492 417 95(99)10–10 931,494 061(21) 1 Дж 1,112 650 056(1)10–17 6,700 535 84(45)109 1 6,241 509 34(14)1012 1 МэВ 1,782 661 845(39)10–30 1,073 544 150(24)10–3 1,602 176 565(35)10–13 1 Название единицы Обозна- чение Определение В единицах СИ Джоуль (СИ) Дж, Дж Работа, совершаемая силой 1 Н при перемещении точки приложения на 1 м в направлении силы[24] = 1 Дж = 1 Н·м = 1 кг·м2/с2 = 1 C·V = 1 Вт·с Эрг (СГС) эрг 1 г·см2/с2 = 1107 Дж Киловатт-час кВт·ч 1 кВт 1 ч = 3,6106 Дж Электронвольт эВ e 1 В 1,602 176 565(35)1019 Дж Ридберг Ry R··c 2,179 8721018 Дж Энергия Хартри Eh me·2·c2 (= 2 Ry) 4.35974394(22)1018 Дж Калория Количество теплоты, необходимое для нагревания 1 грамма воды на 1 градус Цельсия Калория международная калм 4,1868 Дж = 4,1868 Дж Калория средняя 4,190 02 Дж Калория термохимическая калт 4,184 Дж = 4,184 Дж Калория (3,98 °C) кал3,98°C 4,2045 Дж Калория (15 °C) кал15°C 4,1855 Дж = 4,1855 Дж Калория (20 °C) кал20°C 4,1819 Дж Килокалория, большая калория ккал 1 000 калм = 4,1868103 Дж Терми (англ. thermie th 106 калIT = 4,1868106 Дж Единицы, связанные с работой расширения газа Литр-атмосфера л·атм Работа, совершаемая газом при изобарическом расширении на 1 литр при давлении 1 атм (101 325 Па) 1 атм 1 л = 101,325 Дж Куб. см-атмосфера 1 атм 1 см3 = 0,101 325 Дж Куб. фут-атмосфера 1 atm 1 фут3 = 2,869 204 481103 Дж Куб. ярд-атмосфера 1 атм 1 ярд3 = 77,468 520 985 2288103 Дж gallon-atmosphere (imperial) imp gal atm 1 atm 1 gal (imp) = 460,632 569 25 Дж gallon-atmosphere (US) US gal atm 1 atm 1 gal (US) = 383,556 849 0138 Дж horsepower-hour hp·h 1 hp 1 h = 2,684 519 537 696 172 792106 Дж Единицы, связанные с работой силы inch-pound force in lbf g 1 фн 1 дюйм = 0,112 984 829 027 6167 Дж foot-pound force ft lbf g 1 lb 1 ft = 1,355 817 948 331 4004 Дж foot-poundal ft pdl 1 lb·ft2/s2 = 4,214 011 009 380 48102 Дж Термические эквиваленты Эквивалент барреля нефти BOE 5,8106 BTU59 °F 6,12109 Дж Эквивалент тонны угля[англ.] TCE 7 Гкалт = 29,3076109 Дж Эквивалент тонны нефти[англ.] TOE 10 Гкалт = 41,868109 Дж Куб. фут природного газа   1 000 BTUIT = 1,055 055 852 62106 Дж 1 тонна ТНТ тТНТ В качестве условной единицы тротилового эквивалента принята равной 1 Гкал или 4,184 ГДж. Реальная энергия взрыва 1 тонны ТНТ составляет 4,23 ГДж. = 4,184109 Дж Британская термическая единица (БТЕ англ. BTU) Количество теплоты, необходимое для нагревания 1 фунта воды на 1 градус Фаренгейта БТЕ (ИСО) BTUISO 1,0545103 Дж = 1,0545103 Дж БТЕ (международная) BTUIT = 1,055 055 852 62103 Дж БТЕ (средняя) BTUmean 1,055 87103 Дж БТЕ (термохимическая) BTUth 1,054 350103 Дж БТЕ (39 °F) BTU39 °F 1,059 67103 Дж БТЕ (59 °F) BTU59 °F 1,054 804103 Дж = 1,054 804103 Дж БТЕ (60 °F) BTU60 °F 1,054 68103 Дж БТЕ (63 °F) BTU63 °F 1,0546103 Дж Терм (ЕЭС)   100 000 BTUIT = 105.505 585 262106 Дж Терм (США)   100 000 BTU59 °F = 105.4804106 Дж quad   1015 BTUIT = 1.055 055 852 621018 Дж Celsius heat unit (International Table) CHUIT 1 BTUIT 1 K/°R = 1.899 100 534 716103 Дж Power or heat flow rate Power Name of unit Symbol Definition Relation to SI units atmosphere-cubic centimetre per minute atm ccm 1 atm 1 cm3/min = 1.688 75103 W atmosphere-cubic centimetre per second atm ccs 1 atm 1 cm3/s = 0.101 325 W atmosphere-cubic foot per hour atm cfh 1 atm 1 cu ft/h = 0.797 001 244 704 W atmosphere-cubic foot per minute atm·cfm 1 atm 1 cu ft/min = 47.820 074 682 24 W atmosphere-cubic foot per second atm cfs 1 atm 1 cu ft/s = 2.869 204 480 9344103 W BTU (International Table) per hour BTUIT/h 1 BTUIT/h 0.293 071 W BTU (International Table) per minute BTUIT/min 1 BTUIT/min 17.584 264 W BTU (International Table) per second BTUIT/s 1 BTUIT/s = 1.055 055 852 62103 W calorie (International Table) per second calIT/s 1 calIT/s = 4.1868 W erg per second erg/s 1 erg/s = 107 W foot-pound-force per hour ft lbf/h 1 ft lbf/h 3.766 161104 W foot-pound-force per minute ft lbf/min 1 ft lbf/min = 2.259 696 580 552 334102 W foot-pound-force per second ft lbf/s 1 ft lbf/s = 1.355 817 948 331 4004 W horsepower (boiler) bhp 34.5 lb/h 970.3 BTUIT/lb 9.810 657103 W horsepower (European electrical) hp 75 kp·m/s = 736 W horsepower (imperial electrical) hp 746 W = 746 W horsepower (imperial mechanical) hp 550 ft lbf/s = 745.699 871 582 270 22 W horsepower (metric) hp 75 m kgf/s = 735.498 75 W litre-atmosphere per minute L·atm/min 1 atm 1 L/min = 1.688 75 W litre-atmosphere per second L·atm/s 1 atm 1 L/s = 101.325 W lusec lusec 1 L·µmHg/s [14] 1.333104 W poncelet p 100 m kgf/s = 980.665 W square foot equivalent direct radiation sq ft EDR 240 BTUIT/h 70.337 057 W ton of air conditioning   1 t ice melted / 24 h 3 504 W ton of refrigeration (imperial)   1 BTUIT 1 lng tn/lb 10 min/s 3.938 875103 W ton of refrigeration (IT)   1 BTUIT 1 sh tn/lb 10 min/s 3.516 853103 W watt (SI unit) W The power which in one second of time gives rise to one joule of energy.[24] = 1 W = 1 J/s = 1 N·m/s = 1 kg·m2/s3 Action Action Name of unit Symbol Definition Relation to SI units atomic unit of action au /2 1.054 571 681034 J·s[28] Dynamic viscosity Dynamic viscosity Name of unit Symbol Definition Relation to SI units pascal second (SI unit) Pa·s N·s/m2, kg/(m·s) = 1 Pa·s poise (cgs unit) P 1 barye·s = 0.1 Pa·s pound per foot hour lb/(ft·h) 1 lb/(ft·h) 4.133 78910-4 Pa·s pound per foot second lb/(ft·s) 1 lb/(ft·s) 1,488164 Pa·s pound-force second per square foot lbf·s/ft2 1 lbf·s/ft2 47,88026 Pa·s pound-force second per square inch lbf·s/in2 1 lbf·s/in2 6894,757 Pa·s Kinematic viscosity Kinematic viscosity Name of unit Symbol Definition Relation to SI units square foot per second ft2/s 1 ft2/s = 0,09290304 m2/s square metre per second (SI unit) m2/s 1 m2/s = 1 m2/s stokes (cgs unit) St 104 m2/s = 104 m2/s Electric current Electric current Name of unit Symbol Definition Relation to SI units ampere (SI base unit) A The constant current needed to produce a force of 2 10-7 newton per metre between two straight parallel conductors of infinite length and negligible circular cross-section placed one metre apart in a vacuum.[1] = 1 A electromagnetic unit; abampere (cgs unit) abamp 10 A = 10 A esu per second; statampere (cgs unit) esu/s (0.1 A·m/s) / c 3,3356411010 A Electric charge Electric charge Name of unit Symbol Definition Relation to SI units abcoulomb; electromagnetic unit (cgs unit) abC; emu 10 C = 10 C atomic unit of charge au e 1.602 176 4621019 C coulomb (SI unit) C The amount of electricity carried in one second of time by one ampere of current.[24] = 1 C = 1 A·s faraday F 1 mol NA·e 96 485.3383 C statcoulomb; franklin; electrostatic unit (cgs unit) statC; Fr; esu (0.1 A·m) / c 3.335 6411010 C Electric dipole Electric dipole Name of unit Symbol Definition Relation to SI units atomic unit of electric dipole moment ea0   8.478 352 8110-30 C·m[29] coulomb meter C·m   = 1 C · 1 m debye D = 1010 esu· = 3.3356409510-30 C·m [30] Electromotive force, electric potential difference Voltage, electromotive force Name of unit Symbol Definition Relation to SI units abvolt (cgs unit) abV 110-8 V = 110-8 V statvolt (cgs unit) statV c· (1 J/A·m) = 299.792 458 V volt (SI unit) V The difference in electric potential across two points along a conducting wire carrying one ampere of constant current when the power dissipated between the points equals one watt.[24] = 1 V = 1 W/A = 1 kg·m2/(A·s3) Electrical resistance Electrical resistance Name of unit Symbol Definition Relation to SI units ohm (SI unit) The resistance between two points in a conductor when one volt of electric potential difference, applied to these points, produces one ampere of current in the conductor.[24] = 1 = 1 V/A = 1 kg·m2/(A2·s3) Capacitance Capacitor's ability to store charge Name of unit Symbol Definition Relation to SI units farad (SI unit) F The capacitance between two parallel plates that results in one volt of potential difference when charged by one coulomb of electricity.[24] = 1 F = 1 C/V = 1 A2·s4/(kg·m2) Magnetic flux magnetic flux Name of unit Symbol Definition Relation to SI units maxwell (CGS unit) Mx 108 Wb[31] = 110-8 Wb weber (SI unit) Wb Magnetic flux which, linking a circuit of one turn, would produce in it an electromotive force of 1 volt if it were reduced to zero at a uniform rate in 1 second.[24] = 1 Wb = 1 V·s = 1 kg·m2/(A·s2) Magnetic flux density What physicists call Magnetic field is called Magnetic flux density by electrical engineers and magnetic induction by applied mathematicians and electrical engineers. Name of unit Symbol Definition Relation to SI units gauss (CGS unit) G Mx/cm2 = 104 T = 110-4 T [32] tesla (SI unit) T Wb/m2 = 1 T = 1 Wb/m2 = 1 kg/(A·s2) Inductance Inductance Name of unit Symbol Definition Relation to SI units henry (SI unit) H The inductance of a closed circuit that produces one volt of electromotive force when the current in the circuit varies at a uniform rate of one ampere per second.[24] = 1 H = 1 Wb/A = 1 kg·m2/(A·s)2 Temperature Temperature Name of unit Symbol Definition Conversion to kelvin degree Celsius °C °C K 273.15 [K] [°C] + 273.15 degree Delisle °De [K] = 373.15 [°De] 2/3 degree Fahrenheit °F °F °C 9/5 + 32 [K] ([°F] + 459.67) 5/9 degree Newton °N [K] = [°N] 100/33 + 273.15 degree Rankine °R; °R K 9/5 [K] [°R] 5/9 degree Raumur °R [K] = [°R] 5/4 + 273.15 degree Rmer °R [K] = ([°R] 7.5) 40/21 + 273.15 kelvin (SI base unit) K 1/273.16 of the thermodynamic temperature of the triple point of water.[1] 1 K Информация, энтропия Информация, энтропия Название единицы Обозначение Определение В единицах СИ В битах Единица СИ Дж/К Дж/К = 1 Дж/К nat; nip; nepit nat kB = 1.380 650 5(23)10-23 Дж/К Бит; Шеннон бит; Sh ln(2) kB = 9,569 940 (16)10-24 Дж/К = 1 bit ban; hartley ban; Hart ln(10) kB = 3,179 065 3(53)10-23 Дж/К Ниббл 4 бита = 3,827 976 0(64)10-23 Дж/К = 22 бит Байт байт 8 бит = 7,655 952 (13)10-23 Дж/К = 23 бит Килобайт Kб; Кбайт 1 024 байта = 7,839 695 (13)10-20 Дж/К = 213 бит = 8192 бит Often, information entropy is measured in shannons, whereas the (discrete) storage space of digital devices is measured in bits. Thus, uncompressed redundant data occupy more than one bit of storage per shannon of information entropy. The multiples of a bit listed above are usually used with this meaning. Other times the bit is used as a measure of information entropy and is thus a synonym of shannon. Luminous intensity The candela is the preferred nomenclature for the SI unit. Luminous intensity Name of unit Symbol Definition Relation to SI units candela (SI base unit); candle cd The luminous intensity, in a given direction, of a source that emits monochromatic radiation of frequency 5401012 hertz and that has a radiant intensity in that direction of 1/683 watt per steradian.[1] = 1 cd candlepower (new) cp cd The use of candlepower as a unit is discouraged due to its ambiguity. = 1 cd candlepower (old, pre-1948) cp Varies and is poorly reproducible.[33] Approximately 0.981 cd.[14] 0.981 cd Luminance Luminance Name of unit Symbol Definition Relation to SI units candela per square foot cd/ft2 cd/ft2 10,763910417 cd/m2 candela per square inch cd/in2 cd/in2 1550,0031 cd/m2 candela per square metre (SI unit); nit (deprecated[14]) cd/m2 cd/m2 = 1 cd/m2 footlambert fL (1/) cd/ft2 3,4262590996 cd/m2 lambert L (104/) cd/m2 3183,0988618 cd/m2 stilb (CGS unit) sb 104 cd/m2 1104 cd/m2 Luminous flux Luminous flux Name of unit Symbol Definition Relation to SI units lumen (SI unit) lm cd·sr = 1 lm = 1 cd·sr Illuminance Illuminance Name of unit Symbol Definition Relation to SI units footcandle; lumen per square foot fc lm/ft2 = 10,763910417 lx lumen per square inch lm/in2 lm/in2 1550,0031 lx lux (SI unit) lx lm/m2 = 1 lx = 1 lm/m2 phot (CGS unit) ph lm/cm2 = 1104 lx Radiation - source activity Radioactivity Name of unit Symbol Definition Relation to SI units becquerel (SI unit) Bq Number of disintegrations per second = 1 Bq = 1/s curie Ci 3.71010 Bq = 3.71010 Bq [34] rutherford (H) rd 1 MBq = 1106 Bq Please note that although becquerel (Bq) and hertz (Hz) both ultimately refer to the same SI base unit (s1), Hz is used only for periodic phenomena, and Bq is only used for stochastic processes associated with radioactivity.[35] Radiation - exposure Radiation - exposure Name of unit Symbol Definition Relation to SI units roentgen R 1 R 2.5810-4 C/kg[31] = 2.5810-4 C/kg The roentgen is not a SI unit and the NIST strongly discourages its continued use.[36] Radiation - absorbed dose Radiation - absorbed dose Name of unit Symbol Definition Relation to SI units gray (SI unit) Gy 1 J/kg = 1 m2/s2 [37] = 1 Gy rad rad 0.01 Gy[31] = 0.01 Gy Radiation - equivalent dose Radiation - equivalent dose Name of unit Symbol Definition Relation to SI units Rntgen equivalent man rem 0.01 Sv = 0.01 Sv sievert (SI unit) Sv 1 J/kg[35] = 1 Sv Although the definitions for sievert (Sv) and gray (Gy) would seem to indicate that they measure the same quantities, this is not the case. The effect of receiving a certain dose of radiation (given as Gy) is variable and depends on many factors, thus a new unit was needed to denote the biological effectiveness of that dose on the body; this is known as the equivalent dose and is shown in Sv. The general relationship between absorbed dose and equivalent dose can be represented as H = Q · D where H is the equivalent dose, D is the absorbed dose, and Q is a dimensionless quality factor. Thus, for any quantity of D measured in Gy, the numerical value for H measured in Sv may be different.[38] Software tools Home and office computers come with converters in bundled spreadsheet applications or can access free converters via the Internet. Units and measurements can be easily converted using these tools, but only if the units are explicitly defined and the conversion is compatible (e.g., cmHg to kPa). General commercial sources of converters Advanced electronic calculators have unit-conversion functionality. Spreadsheet programs usually provide conversion functions or formulas or the user can write their own. Commercial mathematical, scientific and technical applications often include converters. See also Accuracy and precision English units False precision Imperial units International System of Units Mesures usuelles Metric system Natural units Rounding Significant figures SI prefix (e.g. "kilo-" prefix) Conversion of units of temperature United States customary units Units (software) Units conversion by factor-label Units of measurement Примечания 1 2 3 4 5 6 The International System of Units, Section 2.1 (8 ed.), Bureau International des Poids et Mesures, 2006, Дата обращения: 26 августа 2009 United States Naval Observatory. (2009). Selected Astronomical Constants, 2009. Accessed May 10, 2009 The International Astronomical Union and Astronomical Units P. Kenneth Seidelmann, Ed. (1992). Explanatory Supplement to the Astronomical Almanac. Sausalito, CA: University Science Books. p. 716 and s.v. parsec in Glossary. "NIST Reference on Constants, Units, and Uncertainty."(2006). National Institute of Standards and Technology. Retrieved February 22, 2008. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Lide, D. (Ed.). (1990). Handbook of Chemistry and Physics (71st ed). Boca Raton, FL: CRC Press. Section 1. National Bureau of Standards. (June 30, 1959). Refinement of values for the yard and the pound. Federal Register, viewed September 20, 2006 at National Geodetic Survey web site. 1 2 National Institute of Standards and Technology General Tables of Units of Measurement Klein, Herbert Arthur. (1988). The Science of Measurement: a Historical Survey. Mineola, NY: Dover Publications 0-4862-5839-4. International System of Units, 8th ed. (2006), Bureau International des Poids et Mesures, Section 4.1 Table 8. 1 2 3 Whitelaw, Ian. (2007). A Measure of All Things: The Story of Man and Measurement. New York: Macmillan 0-312-37026-1. p. 152. 1 2 De Vinne, Theodore Low (1900). The practice of typography: a treatise on the processes of type-making, the point system, the names, sizes, styles and prices of plain printing types 2nd ed. New York: The Century Co. p. 142–150. Pasko, Wesley Washington (1894). American dictionary of printing and bookmaking. (1894). New York: Howard Lockwood. p. 521. 1 2 3 4 5 6 Thompson, A. and Taylor, B.N. (2008). Guide for the Use of the International System of Units (SI). National Institute of Standards and Technology Special Publication 811. p. 57. 1 2 3 4 5 US Code of Federal Regulations, Title 21, Section 101.9, Paragraph (b)(5)(viii), Дата обращения: 29 августа 2009 Barry N. Taylor, Ed.,NIST Special Publication 330: The International System of Units (SI) (2001 Edition), Washington: US Government Printing Office, 43,"The 12th Conference Generale des Poids et Mesures (CGPM)…declares that the word “litre” may be employed as a special name for the cubic decimetre". CODATA Value: atomic uint of mass. (2006). National Institute of Standards and Technology. Retrieved 16 September 2008. The Swiss Federal Office for Metrology gives Zentner on a German language web page [1] and quintal on the English translation of that page [2]; the unit is marked "spcifiquement suisse !" 1 2 Pedersen O. (1983). "Glossary" in Coyne, G., Hoskin, M., and Pedersen, O. Gregorian Reform of the Calendar: Proceedings of the Vatican Conference to Commemorate its 400th Anniversary. Vatican Observatory. Available from Astrophysics Data System. Richards, E.G. (1998), Mapping Time, Oxford University Press, pp. 94–95, ISBN 0-19-850413-6 Steel, Duncan (2000), Marking Time, John Wiley & Sons, p. 46, ISBN 0-471-29827-1 CODATA Value: atomic unit of force. (2006). National Institute of Standards and Technology. Retrieved September 14, 2008. 1 2 3 4 5 6 7 8 9 [[Comit International des Poids et Mesures]], Resolution 2, 1946, Дата обращения: 26 августа 2009 {{citation}}: Конфликт с URL–викиссылкой (справка) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 Barry N. Taylor, (April 1 995), Guide for the Use of the International System of Units (SI) (NIST Special Publication 811), Washington, DC: US Government Printing Office, pp. 57–68. Barry N. Taylor, (April 1995), Guide for the Use of the International System of Units (SI) (NIST Special Publication 811), Washington, DC: US Government Printing Office, p. 5. Fundamental Physical Constants - Complete Listing. International System of Units, 8th ed. (2006), Bureau International des Poids et Mesures, Section 4.1 Table 7. The NIST Reference on Constants, Units, and Uncertainty, 2006, Дата обращения: 26 августа 2009 Robert G. Mortimer Physical chemistry,Academic Press, 2000 ISBN 0125083459, page 677 1 2 3 NIST Guide to SI Units, Appendix B.9, Дата обращения: 27 августа 2009 Standard for the Use of the International System of Units (SI): The Modern Metric System IEEE/ASTM SI 10-1997. (1997). New York and West Conshohocken, PA: Institute of Electrical and Electronics Engineers and American Society for Testing and Materials. Tables A.1 through A.5. The NIST Reference on Constants, Units, and Uncertainty, Дата обращения: 28 августа 2009 Ambler Thompson & Barry N. Taylor. (2008). Guide for the Use of the International System of Units (SI). Special Publication 811. Gaithersburg, MD: National Institute of Standards and Technology. p. 10. 1 2 The International System of Units, Section 2.2.2., Table 3 (8 ed.), Bureau International des Poids et Mesures, 2006, Дата обращения: 27 августа 2009 The NIST Guide to the SI (Special Publication 811), section 5.2, 2008, Дата обращения: 27 августа 2009 Ambler Thompson & Barry N. Taylor. (2008). Guide for the Use of the International System of Units (SI). Special Publication 811. Gaithersburg, MD: National Institute of Standards and Technology. p. 5. [[Comit international des poids et mesures]], 2002, Recommendation 2, Дата обращения: 27 августа 2009 {{citation}}: Конфликт с URL–викиссылкой (справка) Unit Converter / Unit Conversions 101  (неопр.). Program. Keisarian Applications. Дата обращения: 24 мая 2011. Ссылки Шаблон:UK-LEG ext How Many? A dictionary of units of measurement NIST: Fundamental physical constants — Non-SI units (35.7 КБ) NIST Guide to SI Units Many conversion factors listed. The Unified Code for Units of Measure Units, Symbols, and Conversions XML Dictionary Units of Measurement Software в каталоге ссылок Curlie (dmoz) Units of Measurement Online Conversion в каталоге ссылок Curlie (dmoz) Шаблон:Systems of measurement Шаблон:SI units navbox