Dictionary · Standards & Units
Quantity value
A number together with a reference (such as a measurement unit) expressing the magnitude of a quantity — 5.34 m, 0.152 kg, or a value on an agreed scale.
Related terms
More from Standards & Units
Conversion factor between units
The ratio of two units for quantities of the same kind — 25.4 mm/in; the numerical value changes, the quantity does not.
VIM (JCGM 200:2012) 1.24
Multiple of a unit
A unit obtained by multiplying a given unit by an integer greater than one — the kilometre from the metre.
VIM (JCGM 200:2012) 1.17
Base quantity
A quantity in a conventionally chosen subset of a system of quantities in which no member can be expressed in terms of the others.
VIM (JCGM 200:2012) 1.4
Secondary measurement standard
A standard established through calibration with respect to a primary standard for a quantity of the same kind.
VIM (JCGM 200:2012) 5.5
Quantity equation
A mathematical relation between quantities in a system of quantities, independent of units — v = l/t regardless of whether metres or inches are used.
VIM (JCGM 200:2012) 1.22
National measurement standard
A standard recognized by national authority to serve, in a state or economy, as the basis for assigning values to other standards of the same kind.
VIM (JCGM 200:2012) 5.3