Search results
Results from the WOW.Com Content Network
The factor–label method can convert only unit quantities for which the units are in a linear relationship intersecting at 0 (ratio scale in Stevens's typology). Most conversions fit this paradigm. An example for which it cannot be used is the conversion between the Celsius scale and the Kelvin scale (or the Fahrenheit scale). Between degrees ...
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).
In 1866, the U.S. Congress passed a law that allowed, but did not require, the use of the metric system in trade and commerce. Included in the law was a table of conversion factors between the customary (i.e. English-derived) and metric units, among them a definition of the meter in terms of the yard, and the kilogram in terms of the pound.
A board foot is a United States and Canadian unit of approximate volume, used for lumber. It is equivalent to 1 inch × 1 foot × 1 foot (144 cu in or 2,360 cm 3). It is also found in the unit of density pounds per board foot. In Australia and New Zealand the terms super foot or superficial foot were formerly used for this unit. The exact ...
The troy ounce is the only unit of the system in current use; it is used for precious metals. Although the troy ounce is larger than its avoirdupois equivalent, the pound is smaller. The obsolete troy pound was divided into 12 ounces, rather than the 16 ounces per pound of the avoirdupois system.
Metric units are units based on the metre, gram or second and decimal (power of ten) multiples or sub-multiples of these. According to Schadow and McDonald, [ 1 ] metric units, in general, are those units "defined 'in the spirit' of the metric system, that emerged in late 18th century France and was rapidly adopted by scientists and engineers.
In July 1959, the various national foot and avoirdupois pound standards were replaced by the international foot of precisely 0.3048 m and the international pound of precisely 0.453 592 37 kg, making conversion between the systems a matter of simple arithmetic.
The slug is a derived unit of mass in a weight-based system of measures, most notably within the British Imperial measurement system and the United States customary measures system. Systems of measure either define mass and derive a force unit or define a base force and derive a mass unit [ 1 ] (cf. poundal , a derived unit of force in a mass ...