Search results
Results from the WOW.Com Content Network
The carat was once specified as four grains in the English-speaking world. Some local units in the English dominion were (re-)defined in simple terms of English units, such as the Indian tola of 180 grains. Tod This was an English weight for wool. [32] It has the alternative spelling forms of tode, todd, todde, toad, and tood. [33]
Units for other physical quantities are derived from this set as needed. In English Engineering Units, the pound-mass and the pound-force are distinct base units, and Newton's Second Law of Motion takes the form = where is the acceleration in ft/s 2 and g c = 32.174 lb·ft/(lbf·s 2).
The US Customary system of units was developed and used in the United States after the American Revolution, based on a subset of the English units used in the Thirteen Colonies; it is the predominant system of units in the United States and in U.S. territories (except for Puerto Rico and Guam, where the metric system, which was introduced when ...
United States customary units form a system of measurement units commonly used in the United States and most U.S. territories [1] since being standardized and adopted in 1832. [2] The United States customary system developed from English units that were in use in the British Empire before the U.S. became an
The former Weights and Measures office in Seven Sisters, London (590 Seven Sisters Road). The imperial system of units, imperial system or imperial units (also known as British Imperial [1] or Exchequer Standards of 1826) is the system of units first defined in the British Weights and Measures Act 1824 and continued to be developed through a series of Weights and Measures Acts and amendments.
The main units of length (inch, foot, yard and international mile) were the same in the US, though the US rarely uses some of the intermediate units today, such as the (surveyor's) chain (22 yards) and the furlong (220 yards). At one time, the definition of the nautical mile was based on the surface area of the Clarke ellipsoid.
Conversion of units is the conversion of the unit of measurement in which a quantity is expressed, typically through a multiplicative conversion factor that changes the unit without changing the quantity. This is also often loosely taken to include replacement of a quantity with a corresponding quantity that describes the same physical property.
The SI units are defined by declaring that seven defining constants [1]: 125–129 have certain exact numerical values when expressed in terms of their SI units. The realisation of the definition of a unit is the procedure by which the definition may be used to establish the value and associated uncertainty of a quantity of the same kind as the ...