UNITS & CONSTANTS

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SymbolDescriptionSubjectLevelFrequencyAliasesLaTeXUnicodeRelatedExampleCommon fields
s denotes second in si base units.SI Base UnitsIntermediateFrequentSecond 秒\mathrm{s}U+0073—t = 12 sScience, engineering, metrology, education
m denotes metre in si base units.SI Base UnitsIntermediateFrequentMetre 米\mathrm{m}U+006D—l = 3 mScience, engineering, metrology, education
kg denotes kilogram in si base units.SI Base UnitsIntermediateFrequentKilogram 千克\mathrm{kg}U+006B + U+0067—m = 2 kgScience, engineering, metrology, education
A denotes ampere in si base units.SI Base UnitsIntermediateFrequentAmpere 安培\mathrm{A}U+0041—I = 1 AScience, engineering, metrology, education
K denotes kelvin in si base units.SI Base UnitsIntermediateFrequentKelvin 开尔文\mathrm{K}U+004B—T = 300 KScience, engineering, metrology, education
mol denotes mole in si base units.SI Base UnitsIntermediateFrequentMole 摩尔\mathrm{mol}U+006D + U+006F + U+006C—n = 1 molScience, engineering, metrology, education
cd denotes candela in si base units.SI Base UnitsIntermediateFrequentCandela 坎德拉\mathrm{cd}U+0063 + U+0064—Iᵥ = 1 cdScience, engineering, metrology, education
rad denotes radian in si derived units.SI Derived UnitsIntermediateFrequentRadian 弧度\mathrm{rad}U+0072 + U+0061 + U+0064—θ = 2 radScience, engineering, metrology, education
sr denotes steradian in si derived units.SI Derived UnitsIntermediateFrequentSteradian 球面度\mathrm{sr}U+0073 + U+0072—Ω = 1 srScience, engineering, metrology, education
Hz denotes hertz in si derived units.SI Derived UnitsIntermediateFrequentHertz 赫兹\mathrm{Hz}U+0048 + U+007A—f = 50 HzScience, engineering, metrology, education
N denotes newton in si derived units.SI Derived UnitsIntermediateFrequentNewton 牛顿\mathrm{N}U+004E—F = 10 NScience, engineering, metrology, education
Pa denotes pascal in si derived units.SI Derived UnitsIntermediateFrequentPascal 帕斯卡\mathrm{Pa}U+0050 + U+0061—p = 101325 PaScience, engineering, metrology, education
J denotes joule in si derived units.SI Derived UnitsIntermediateFrequentJoule 焦耳\mathrm{J}U+004A—E = 20 JScience, engineering, metrology, education
W denotes watt in si derived units.SI Derived UnitsIntermediateFrequentWatt 瓦特\mathrm{W}U+0057—P = 60 WScience, engineering, metrology, education
C denotes coulomb in si derived units.SI Derived UnitsIntermediateFrequentCoulomb 库仑\mathrm{C}U+0043—q = 1 CScience, engineering, metrology, education
V denotes volt in si derived units.SI Derived UnitsIntermediateFrequentVolt 伏特\mathrm{V}U+0056—U = 5 VScience, engineering, metrology, education
F denotes farad in si derived units.SI Derived UnitsIntermediateFrequentFarad 法拉\mathrm{F}U+0046—C = 1 FScience, engineering, metrology, education
Ω denotes ohm in si derived units.SI Derived UnitsIntermediateFrequentOhm 欧姆\OmegaU+03A9—R = 100 ΩScience, engineering, metrology, education
S denotes siemens in si derived units.SI Derived UnitsIntermediateFrequentSiemens 西门子\mathrm{S}U+0053—G = 1 SScience, engineering, metrology, education
Wb denotes weber in si derived units.SI Derived UnitsIntermediateFrequentWeber 韦伯\mathrm{Wb}U+0057 + U+0062—Φ = 1 WbScience, engineering, metrology, education
T denotes tesla in si derived units.SI Derived UnitsIntermediateFrequentTesla 特斯拉\mathrm{T}U+0054—B = 1 TScience, engineering, metrology, education
H denotes henry in si derived units.SI Derived UnitsIntermediateFrequentHenry 亨利\mathrm{H}U+0048—L = 1 HScience, engineering, metrology, education
°C denotes degree celsius in si derived units.SI Derived UnitsIntermediateFrequentDegree Celsius 摄氏度{}^\circ\mathrm{C}U+00B0 + U+0043—θ = 20 °CScience, engineering, metrology, education
lm denotes lumen in si derived units.SI Derived UnitsIntermediateFrequentLumen 流明\mathrm{lm}U+006C + U+006D—Φᵥ = 800 lmScience, engineering, metrology, education
lx denotes lux in si derived units.SI Derived UnitsIntermediateFrequentLux 勒克斯\mathrm{lx}U+006C + U+0078—Eᵥ = 500 lxScience, engineering, metrology, education
Bq denotes becquerel in si derived units.SI Derived UnitsIntermediateFrequentBecquerel 贝可勒尔\mathrm{Bq}U+0042 + U+0071—A = 1 BqScience, engineering, metrology, education
Gy denotes gray in si derived units.SI Derived UnitsIntermediateFrequentGray 戈瑞\mathrm{Gy}U+0047 + U+0079—D = 1 GyScience, engineering, metrology, education
Sv denotes sievert in si derived units.SI Derived UnitsIntermediateFrequentSievert 希沃特\mathrm{Sv}U+0053 + U+0076—H = 1 SvScience, engineering, metrology, education
kat denotes katal in si derived units.SI Derived UnitsIntermediateFrequentKatal 开特\mathrm{kat}U+006B + U+0061 + U+0074—z = 1 katScience, engineering, metrology, education
Q denotes quetta in si prefixes.SI PrefixesIntermediateFrequentQuetta 昆\mathrm{Q}U+0051—1 Q = 10³⁰Science, engineering, metrology, education
R denotes ronna in si prefixes.SI PrefixesIntermediateFrequentRonna 容\mathrm{R}U+0052—1 R = 10²⁷Science, engineering, metrology, education
Y denotes yotta in si prefixes.SI PrefixesIntermediateFrequentYotta 尧\mathrm{Y}U+0059—1 Y = 10²⁴Science, engineering, metrology, education
Z denotes zetta in si prefixes.SI PrefixesIntermediateFrequentZetta 泽\mathrm{Z}U+005A—1 Z = 10²¹Science, engineering, metrology, education
E denotes exa in si prefixes.SI PrefixesIntermediateFrequentExa 艾\mathrm{E}U+0045—1 E = 10¹⁸Science, engineering, metrology, education
P denotes peta in si prefixes.SI PrefixesIntermediateFrequentPeta 拍\mathrm{P}U+0050—1 P = 10¹⁵Science, engineering, metrology, education
T denotes tera in si prefixes.SI PrefixesIntermediateFrequentTera 太\mathrm{T}U+0054—1 T = 10¹²Science, engineering, metrology, education
G denotes giga in si prefixes.SI PrefixesIntermediateFrequentGiga 吉\mathrm{G}U+0047—1 G = 10⁹Science, engineering, metrology, education
M denotes mega in si prefixes.SI PrefixesIntermediateFrequentMega 兆\mathrm{M}U+004D—1 M = 10⁶Science, engineering, metrology, education
k denotes kilo in si prefixes.SI PrefixesIntermediateFrequentKilo 千\mathrm{k}U+006B—1 k = 10³Science, engineering, metrology, education
h denotes hecto in si prefixes.SI PrefixesIntermediateFrequentHecto 百\mathrm{h}U+0068—1 h = 10²Science, engineering, metrology, education
da denotes deca in si prefixes.SI PrefixesIntermediateFrequentDeca 十\mathrm{da}U+0064 + U+0061—1 da = 10¹Science, engineering, metrology, education
d denotes deci in si prefixes.SI PrefixesIntermediateFrequentDeci 分\mathrm{d}U+0064—1 d = 10⁻¹Science, engineering, metrology, education
c denotes centi in si prefixes.SI PrefixesIntermediateFrequentCenti 厘\mathrm{c}U+0063—1 c = 10⁻²Science, engineering, metrology, education
m denotes milli in si prefixes.SI PrefixesIntermediateFrequentMilli 毫\mathrm{m}U+006D—1 m = 10⁻³Science, engineering, metrology, education
μ denotes micro in si prefixes.SI PrefixesIntermediateFrequentMicro 微\muU+03BC—1 μ = 10⁻⁶Science, engineering, metrology, education
n denotes nano in si prefixes.SI PrefixesIntermediateFrequentNano 纳\mathrm{n}U+006E—1 n = 10⁻⁹Science, engineering, metrology, education
p denotes pico in si prefixes.SI PrefixesIntermediateFrequentPico 皮\mathrm{p}U+0070—1 p = 10⁻¹²Science, engineering, metrology, education
f denotes femto in si prefixes.SI PrefixesIntermediateFrequentFemto 飞\mathrm{f}U+0066—1 f = 10⁻¹⁵Science, engineering, metrology, education
a denotes atto in si prefixes.SI PrefixesIntermediateFrequentAtto 阿\mathrm{a}U+0061—1 a = 10⁻¹⁸Science, engineering, metrology, education
z denotes zepto in si prefixes.SI PrefixesIntermediateFrequentZepto 仄\mathrm{z}U+007A—1 z = 10⁻²¹Science, engineering, metrology, education
y denotes yocto in si prefixes.SI PrefixesIntermediateFrequentYocto 幺\mathrm{y}U+0079—1 y = 10⁻²⁴Science, engineering, metrology, education
r denotes ronto in si prefixes.SI PrefixesIntermediateFrequentRonto 柔\mathrm{r}U+0072—1 r = 10⁻²⁷Science, engineering, metrology, education
q denotes quecto in si prefixes.SI PrefixesIntermediateFrequentQuecto 亏\mathrm{q}U+0071—1 q = 10⁻³⁰Science, engineering, metrology, education
c denotes speed of light in vacuum in scientific constants.Scientific ConstantsIntermediateFrequentSpeed of light in vacuum 真空光速cU+0063—c = 299792458 m·s⁻¹Science, engineering, metrology, education
h denotes planck constant in scientific constants.Scientific ConstantsIntermediateFrequentPlanck constant 普朗克常量hU+0068—h = 6.62607015×10⁻³⁴ J·sScience, engineering, metrology, education
e denotes elementary charge in scientific constants.Scientific ConstantsIntermediateFrequentElementary charge 元电荷eU+0065—e = 1.602176634×10⁻¹⁹ CScience, engineering, metrology, education
k denotes boltzmann constant in scientific constants.Scientific ConstantsIntermediateFrequentBoltzmann constant 玻尔兹曼常量kU+006B—k = 1.380649×10⁻²³ J·K⁻¹Science, engineering, metrology, education
Nᴬ denotes avogadro constant in scientific constants.Scientific ConstantsIntermediateFrequentAvogadro constant 阿伏伽德罗常量N_AU+004E + U+1D2C—Nᴬ = 6.02214076×10²³ mol⁻¹Science, engineering, metrology, education
G denotes newtonian constant of gravitation in scientific constants.Scientific ConstantsIntermediateFrequentNewtonian constant of gravitation 万有引力常量GU+0047—F = Gm₁m₂/r²Science, engineering, metrology, education
R denotes molar gas constant in scientific constants.Scientific ConstantsIntermediateFrequentMolar gas constant 摩尔气体常量RU+0052—pV = nRTScience, engineering, metrology, education
α denotes fine-structure constant in scientific constants.Scientific ConstantsIntermediateFrequentFine-structure constant 精细结构常量\alphaU+03B1—α ≈ 1/137Science, engineering, metrology, education
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