Measurement Units & Physical Quantities

← Back to Domain-Specific Families

Abstractions about units, dimensions, physical quantities, measurement scales, metrication, numerical precision, and historical systems of measure.

14 abstractions in this family — domain-specific abstractions that sit near one another in structural-signature space (k-means over structural-signature embeddings). Each is shown with its short description.

• Ancient Mesopotamian units of measurement — Historically changing Mesopotamian systems for measuring length, area, volume, mass and time through linked metrological standards.
• Cape foot — A historical South African unit of length equal to the Rijnland foot and used especially in surveying and land records.
• Degree (angle) — A plane-angle unit equal to one three-hundred-sixtieth of a full rotation.
• Femtometre — The SI unit of length equal to 10 to the minus 15 metres, conventionally symbolized fm.
• Heaviside–Lorentz units — A rationalized electromagnetic unit convention absorbing vacuum constants and distributing geometric factors so Maxwell’s equations have symmetric field normalization.
• Japanese units of measurement — The traditional Japanese shakkanhō system of length, area, volume, mass, and related units standardized relative to metric definitions.
• Length — A one-dimensional measure of spatial extent or distance, expressed relative to a unit and specialized as height, width, path length or other geometry-dependent quantities.
• Metrication — The institutional transition from customary or local measurement systems to the metric system through legal standards, technical conversion, education and changed everyday practice.
• Mile — A family of historically related length units whose modern international form is exactly 1,609.344 metres, with qualified statute, nautical, survey and geographic variants requiring explicit convention.
• Per cent mille — A unit equal to one hundred-thousandth of a whole, written pcm in some engineering and epidemiological contexts and equal to one-thousandth of a percent.
• Physical quantity — A measurable property of a phenomenon, body or substance represented by a numerical value together with a measurement unit and quantity kind.
• Scale of temperature — A calibrated mapping from thermometric states to ordered numerical temperature values under a declared reference and unit.
• Siemens (unit) — The SI derived unit of electric conductance, admittance and susceptance, equal to one reciprocal ohm and symbolized S.
• Significant figures — Digits retained in a measured or calculated quantity to communicate precision under a stated measurement and rounding convention.