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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33 results for “Base quantity”
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…
Documents
SP 330 — International System of Units
…Base quantities and dimensions used in the SI Base quantity Typical symbol for quantity Symbol for dimension time t T length l, x, r…
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…
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
Quantity dimension
The expression of a quantity's dependence on the base quantities as a product of powers of their dimensions — force has dimension L·M…
Dictionary
Base unit
A measurement unit adopted by convention for a base quantity — in the SI: second, metre, kilogram, ampere, kelvin, mole, candela. VIM (JCGM 200:2012…
Documents
SP 811 — Guide for the Use of SI Units
Guide for the Use of the International System of Units (SI) 4 4.1 SI base units Table 1 gives the seven base quantities…
Documents
SP 250-95 — Photometric Calibrations
…as an SI base unit, luminous flux (lumen) is perhaps the most fundamental photometric quantity, as the four other photometric quantities are defined in…
Dictionary
System of units
A set of base and derived units, with their multiples and submultiples, defined under given rules for a given system of quantities. VIM (JCGM…