Primary
Physical Quantity ○꠹｜Definition｜1st｜20260110205401-00-⌔
Physical quantity
A physical quantity (or simply quantity)12 is a property of a material or system that can be quantified by measurement. A physical quantity can be expressed as a value, which is a pair of a numerical value and a unit of measurement. For example, the physical quantity mass, symbol m, can be quantified as m = n kg, where n is the numerical value and kg is the unit symbol (for kilogram). Vector quantities have, besides numerical value and unit, direction or orientation in space.
Printed 2026-06-28.
Link to original Footnotes
“ISO 80000-1:2009(en) Quantities and units — Part 1: General”. International Organization for Standardization. Retrieved 2023-05-12. ↩
“The concept ‘quantity’ may be generically divided into, e.g. ‘physical quantity’, ‘chemical quantity’, and ‘biological quantity’, or ‘base quantity’ and ‘derived quantity’.” ↩
Secondary
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