Home > Terms > English (EN) > International System of Units (SI)
International System of Units (SI)
The modern form of the metric system, which has been adopted by the United States and most other nations. Note: The SI is constructed from seven base units for independent physical quantities. Tables showing these values are included below and are current as of Fall 1995. SI Prefixes. The common metric prefixes are: Multiplication Factor Prefix Name Prefix Symbol 1 000 000 000 000 000 000 000 000 = 1024 yotta Y 1 000 000 000 000 000 000 000 = 1021 zetta Z 1 000 000 000 000 000 000 = 1018 exa E 1 000 000 000 000 000 = 1015 peta P 1 000 000 000 000 = 1012 tera T 1 000 000 000 = 109 giga G 1 000 000 = 106 mega M 1 000 = 103 kilo k 100 = 102 hecto h 10 = 101 deka da 0. 1 = 10-1 deci d 0. 01 = 10-2 centi c 0. 001 = 10-3 milli m 0. 000 001 = 10-6 micro 0. 000 000 001 = 10-9 nano n 0. 000 000 000 001 = 10-12 pico p 0. 000 000 000 000 001 = 10-15 femto f 0. 000 000 000 000 000 001 = 10-18 atto a 0. 000 000 000 000 000 000 001 = 10-21 zepto z 0. 000 000 000 000 000 000 000 001 = 10-24 yocto y SI Base Units: Quantity Unit Name Unit Symbol length meter m mass kilogram kg time second s electric current ampere A thermodynamic temperature kelvin K amount of substance mole mol luminous intensity candela cd SI derived units. Derived units are formed by combining base units and other derived units according to the algebraic relations linking the corresponding quantities. The symbols for derived units are obtained by means of the mathematical signs for multiplication, division, and use of exponents. For example, the SI unit for velocity is the meter per second (m/s or m•s-1,) and that for angular velocity is the radian per second (rad/s or rad•s-1. ) Some derived SI units have been given special names and symbols, as listed in this table: Quantity Unit Name Unit Symbol Expression in Terms of Other SI Units Absorbed dose, specific energy imparted, kerma, absorbed dose index gray Gy J/kg Activity (of a radionuclide) becquerel Bq 1/s Celsius temperature degree Celsius C K Dose equivalent sievert Sv J/kg Electric capacitance farad F C/V Electric charge, quantity of electricity coulomb C A•s Electric conductance siemens S A/V Electric inductance henry H Wb/A Electric potential, potential difference, electromotive force volt V W/A Electric resistance ohm V/A Energy, work, quantity of heat joule J N•m Force newton N kg•m/s2 Frequency (of a periodic phenomenon) hertz Hz 1/s Illuminance lux lx lm/m2 Luminous flux lumen lm cd•sr Magnetic flux weber Wb V•s Magnetic flux density tesla T Wb/m2 Plane angle radian rad m/m Power, radiant flux watt W J/s Pressure, stress pascal Pa N/m2 Solid angle steradian sr m2/m2
- Part of Speech: noun
- Synonym(s):
- Blossary:
- Industry/Domain: Telecommunications
- Category: General telecom
- Company: ATIS
- Product:
- Acronym-Abbreviation:
Other Languages:
Member comments
Terms in the News
Billy Morgan
Sports; Snowboarding
The British snowboarder Billy Morgan has landed the sport’s first ever 1800 quadruple cork. The rider, who represented Great Britain in the 2014 Winter Olympics in Sochi, was in Livigno, Italy, when he achieved the man-oeuvre. It involves flipping four times, while body also spins with five complete rotations on a sideways or downward-facing axis. The trick ...
Marzieh Afkham
Broadcasting & receiving; News
Marzieh Afkham, who is the country’s first foreign ministry spokeswoman, will head a mission in east Asia, the state news agency reported. It is not clear to which country she will be posted as her appointment has yet to be announced officially. Afkham will only be the second female ambassador Iran has had. Under the last shah’s rule, Mehrangiz Dolatshahi, a ...
Weekly Packet
Language; Online services; Slang; Internet
Weekly Packet or "Paquete Semanal" as it is known in Cuba is a term used by Cubans to describe the information that is gathered from the internet outside of Cuba and saved onto hard drives to be transported into Cuba itself. Weekly Packets are then sold to Cuban's without internet access, allowing them to obtain information just days - and sometimes hours - after it ...
Asian Infrastructure Investment Bank (AIIB)
Banking; Investment banking
The Asian Infrastructure Investment Bank (AIIB) is an international financial institution established to address the need in Asia for infrastructure development. According to the Asian Development Bank, Asia needs $800 billion each year for roads, ports, power plants or other infrastructure projects before 2020. Originally proposed by China in 2013, a signing ...
Spartan
Online services; Internet
Spartan is the codename given to the new Microsoft Windows 10 browser that will replace Microsoft Windows Internet Explorer. The new browser will be built from the ground up and disregard any code from the IE platform. It has a new rendering engine that is built to be compatible with how the web is written today. The name Spartan is named after the ...
Featured Terms
fasting
Fasting is primarily an act of willing abstinence or reduction from certain or all food, drink, or both, for a period of time. An absolute fast is ...
Contributor
Featured blossaries
Browers Terms By Category
- Cultural anthropology(1621)
- Physical anthropology(599)
- Mythology(231)
- Applied anthropology(11)
- Archaeology(6)
- Ethnology(2)
Anthropology(2472) Terms
- Software engineering(1411)
- Productivity software(925)
- Unicode standard(481)
- Workstations(445)
- Computer hardware(191)
- Desktop PC(183)
Computer(4168) Terms
- General jewelry(850)
- Style, cut & fit(291)
- Brands & labels(85)
- General fashion(45)
Fashion(1271) Terms
- Organic chemistry(2762)
- Toxicology(1415)
- General chemistry(1367)
- Inorganic chemistry(1014)
- Atmospheric chemistry(558)
- Analytical chemistry(530)
Chemistry(8305) Terms
- Cables & wires(2)
- Fiber optic equipment(1)