Density conversion family
Mass density is mass divided by volume; its coherent SI unit is kilogram per cubic metre (kg/m³).
Five named units
| Unit | Symbol | Factor to base | Relationship | Definition and variant |
|---|---|---|---|---|
| kilogram per cubic meter | kg/m³ | 1 | defined | Kilogram per cubic metre is the coherent SI unit of mass density. Named variant: Mass density. The base factor is exactly 1 by the family base-unit choice. |
| gram per cubic centimeter | g/cm³ | 1000 | exact | Because 1 g = 10^-3 kg and 1 cm³ = 10^-6 m³, 1 g/cm³ = 1000 kg/m³ exactly. Named variant: Mass density; cubic centimetre denominator. The factor follows exactly from SI decimal prefixes. |
| kilogram per liter | kg/L | 1000 | exact | The litre is exactly one cubic decimetre or 10^-3 m³, so 1 kg/L = 1000 kg/m³ exactly. Named variant: Mass density using litre volume. The litre-to-cubic-metre relationship is exact. |
| pound per cubic foot | lb/ft³ | 16.01846337396 | approximate | This unit uses one avoirdupois pound per cubic international foot; its exact-reference conversion begins 16.018463373960139... kg/m³. Named variant: Avoirdupois pound per cubic international foot; not pound-force or survey-foot volume. The preserved application factor is a rounded decimal of the exact value derived from 0.45359237 kg and (0.3048 m)³. |
| pound per US gallon | lb/US gal | 119.826427316 | approximate | This unit uses one avoirdupois pound per U.S. liquid gallon, where 1 U.S. gal = 231 in³ = 0.003785411784 m³ exactly. Named variant: U.S. liquid gallon only; not the British Imperial gallon. The preserved application factor is truncated relative to the exact-reference quotient 119.8264273168966... kg/m³; this discrepancy is documented rather than silently changing the generator factor. |
Every ordered pair
This family is machine-reviewed-pending-human. Automated checks verify structure, factor parity and source references; they do not constitute human or specialist approval.
