Dictionary
Derived quantity
A quantity in a system of quantities defined in terms of the base quantities of that system — speed, force, pressure. VIM (JCGM 200:2012…
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94 results for “Quantity”
Dictionary
Quantity of dimension one
A quantity whose dimension has all base-quantity exponents equal to zero — refractive index, strain, a ratio of like quantities; often loosely called "dimensionless…
Dictionary
International System of Quantities (ISQ)
The system of quantities based on the seven base quantities: length, mass, time, electric current, thermodynamic temperature, amount of substance, and luminous intensity — the…
Dictionary
True quantity value
The quantity value consistent with the definition of the quantity. In practice unknowable; measurement estimates it with stated uncertainty. VIM (JCGM 200:2012) 2…
Dictionary
Numerical quantity value
The number in a quantity value — the 5.34 in 5.34 m: the ratio of the quantity to its unit. VIM (JCGM 200…
Dictionary
Kind of quantity
The aspect common to mutually comparable quantities — length, mass, and energy are kinds; diameter and wavelength are both quantities of the kind length. VIM…
Dictionary
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…
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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…
Dictionary
Output quantity in a measurement model
The quantity whose measured value is calculated from the input quantity values using the model — the measurand's seat in the mathematics. VIM (JCGM…
Dictionary
Conventional quantity value
A quantity value attributed to a quantity by agreement for a given purpose — the conventional value of local gravity, or the conventional mass of…