SI units


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Related to SI units: Metric units

SI units

An internationally agreed system of coherent metric units, increasingly used for all scientific and technical purposes. It was developed from the MKS system of units and replaces the CGS and Imperial systems of units. There are seven base units that are arbitrarily defined and dimensionally independent (see Table 1). These include the kelvin and the second. The meter has been redefined but is still a base unit. The base units can be combined by multiplication and/or division to derive other units, such as the watt or the newton (see Table 2). A set of prefixes, including kilo- and micro-, can be used to form decimal multiples or submultiples of the units (see Table 3). Any physical quantity may then be expressed in terms of a number multiplied by the appropriate SI unit for that quantity.

International System of Units (SI)

A system of units based on the following fundamental quantities: metre, kilogram, second, ampere, kelvin, candela, and mole.

SI units

(Système International d'Unites; International System of Units) A system of standard units of measurement finalized at the 14th General Conference on Weights and Measures in 1971. It is based on seven units of measure, including three from the MKS system (meter-kilogram-second), the ampere for electrical current, the Kelvin for temperature, the candela for luminosity and the mole for molecular weight. See MKS system, amp, Kelvin, candela and mole.

BASIC SI UNITS Quantity        Unit of Measurement

 length (l)      meter (m)
 mass (m)        kilogram (kg)
 time (t)        second (s)
 current (I)     ampere (A)
 temperature     kelvin (K)
 atomic weight   mole (mol)
 luminosity      candela (cd) 


 DERIVED SI UNITS Quantity             Unit of Measurement

 force (f)            newton (N)
 work (W)             joule (J)
 power (P)            watt (W)
 pressure (P)         pascal (pa)
 frequency (f)        Hertz (Hz)
 electric charge (Q)  coulomb (C)
 potential (V)        volt (V)
 capacitance (C)      Farad (F)
 resistance (R)       ohm
References in periodicals archive ?
It is vital for countries that convert to SI units to avoid jeopardizing the health of patients, and the well-known adage primum non nocere (first do no harm) should not be forgotten.
SI coherent derived unit Derived Name Symbol Expressed in Expressed in quantity terms of other terms of SI SI units base units solid angle steradian sr [m.
cSv = centisievert, the SI unit of dose equivalent.
The product data is presented in graphical and tabular format, with results normalized to SI units, retaining the familiar format of the first edition and allowing easy comparison between materials and test conditions.
Standard languages in the controller are English, Spanish and French, as well as SI units of measure.
30, 1996 - the deadline for submitting federal-aid designs in SI units.
If I have to pick the one item that annoyed me, it was his section on SI units in Chapter 4.
Now includes SI units throughout alongside imperial, and now accompanied by online calculation tools New to this edition;
Tenders are invited for Spares For Static Inverter Si Units Siemens Make, 180 Kva For Wag-5/Wag-7 Type Loco As Per List Enclosed In Annexure A And B Under Para D Of Tender Schedule.
This current study has aimed to establish, within a mixed primary and secondary care setting, if this move to reporting just SI units subsequently led to a change in Hb [A.
In the UAE, all the SI units are commonly used with the exception of textile measurements of yard and exported goods using inches and feet.