Units of measurement in the context of "Dimensional analysis"

The square kilometre (square kilometer in American spelling; symbol: km) is a multiple of the square metre, the SI unit of area or surface area. In the SI unit of area (m), 1 km is equal to 1M(m).

A fathom is a unit of length in the imperial and U.S. customary systems equal to 6 feet (1.8288 m), used especially for measuring the depth of water. The fathom is neither an international standard (SI) unit, nor an internationally accepted non-SI unit. Historically, it was the maritime measure of depth in the English-speaking world but, apart from within the US, charts now use metres.

There are two yards (6 feet) in an imperial fathom. Originally the span of a man's outstretched arms, the size of a fathom has varied slightly depending on whether it was defined as a thousandth of an (Admiralty) nautical mile or as a multiple of the imperial yard. Formerly, the term was used for any of several units of length varying around 5–5+1⁄2 feet (1.5–1.7 m).

The cent is a monetary unit of many national currencies that equals a hundredth (1⁄100) of the basic monetary unit. The word derives from the Latin centum, 'hundred'.

The cent sign is commonly a simple minuscule (lower case) letter c. In North America, the c is crossed by a diagonal or vertical stroke (depending on typeface), yielding the character ¢.

The kilometre per hour (SI symbol: km/h; non-SI abbreviations: kph, kmph, km/hr) is a unit of speed, expressing the number of kilometres travelled in one hour.

Size in general is the magnitude or dimensions of a thing. More specifically, geometrical size (or spatial size) can refer to three geometrical measures: length, area, or volume. Length can be generalized to other linear dimensions (width, height, diameter, perimeter). Size can also be measured in terms of mass, especially when assuming a density range.

In mathematical terms, "size is a concept abstracted from the process of measuring by comparing a longer to a shorter". Size is determined by the process of comparing or measuring objects, which results in the determination of the magnitude of a quantity, such as length or mass, relative to a unit of measurement. Such a magnitude is usually expressed as a numerical value of units on a previously established spatial scale, such as meters or inches.

Technical drawing, drafting or drawing, is the act and discipline of composing drawings that visually communicate how something functions or is constructed.

Technical drawing is essential for communicating ideas in industry and engineering.To make the drawings easier to understand, people use familiar symbols, perspectives, units of measurement, notation systems, visual styles, and page layout. Together, such conventions constitute a visual language and help to ensure that the drawing is unambiguous and relatively easy to understand. Many of the symbols and principles of technical drawing are codified in an international standard called ISO 128.

The inch (symbol: in or ″) is a unit of length in the British Imperial and the United States customary systems of measurement. It is equal to ⁠1/36⁠ yard or ⁠1/12⁠ of a foot. Derived from the Roman uncia ("twelfth"), the word inch is also sometimes used to translate similar units in other measurement systems, usually understood as deriving from the width of the human thumb.

Standards for the exact length of an inch have varied in the past, but since the adoption of the international yard during the 1950s and 1960s the inch has been based on the metric system and defined as exactly 25.4 mm.

The nanometre (international spelling as used by the International Bureau of Weights and Measures; SI symbol: nm), or nanometer (American spelling), is a unit of length in the International System of Units (SI), equal to one billionth (short scale) or one thousand million (long scale) of a metre (0.000000001 m) and to 1000 picometres. One nanometre can be expressed in scientific notation as 1 × 10 m and as ⁠1/1000000000⁠ m.

Luminance is a photometric measure of the luminous intensity per unit area of light travelling in a given direction. It describes the amount of light that passes through, is emitted from, or is reflected from a particular area, and falls within a given solid angle.

The procedure for conversion from spectral radiance to luminance is standardized by the CIE and ISO.

In science and engineering, the parts-per notation is a set of pseudo-units to describe the small values of miscellaneous dimensionless quantities, e.g. mole fraction or mass fraction.

Since these fractions are quantity-per-quantity measures, they are pure numbers with no associated units of measurement. Commonly used are