A unit object has two parts: a real number and a unit expression (a single unit or a multiplicative combination of units). The two parts are linked by the character _ ("underscore"). For example 2_m for 2 meters. For composite units, parenthesis must be used, e.g. 1_(m*s). See table 10.1 for a list of the basic units.
Name Description Name Description _A Ampere _ha Hectare _Angstrom Angstrom _hp Horsepower _Bq Becquerel _in Inch _Btu Btu British thermal unit _inH20 Inches of water, 60 degrees Fahrenheit _Ci Curie _inHg Inches of mercury, 0 degree Celsius _F Farad _j Day _Fdy Faraday _kWh Kilowatt-hour _Gal Gal (0.01 m/s2) _kg Kilogram _Gy Gray _kip Kilopound-force _H Henry _km Kilometre _Hz Hertz _knot nautical miles per hour _J Joule _kph Kilometers per hour _K Kelvin _l Liter _Kcal Kilocalorie _lam Lambert _MHz Megahertz _lb pound (1 pound = 16 oz) _MW Megawatt _lbf Pound-force _MeV Megaelectronvolt _lbmol Pound-mole _N Newton _lbt Troy pound _Ohm Ohm _lep Liter of oil equivalent _P Poise (measures viscosity) _liqpt US liquid pint (1 US gallon = 8 US liquid pints) _Pa Pascal _lm Lumen _R Roentgen _lx Lux _Rankine Degree Rankine _lyr Light year _S Siemens _m Metre (unit) _St Stokes _mho Mho _Sv Sievert _miUS US statute mile _T Tesla _mi^2 Square international mile. _V Volt _mil Mil _W Watt _mile International mile _Wb Weber _mille Nautical mile _Wh Watt-hour _ml millilitre _a Are (100 m2) _mm Millimetre _acre Acre _mmHg Millimeter of mercury (torr), 0 degree Celsius _arcmin Minute of arc _mn Minute _arcs Second of arc _mol Mole _atm Atmosphere _mph Miles per hour _au Astronomical unit _oz Ounce _b Barn _ozUK UK fluid ounce _bar Bar _ozfl US fluid ounce _bbl Barrel _ozt Troy ounce _bblep Barrel of oil equivalent _pc Parsec _bu Bushel (1 bushel=8 gallons UK) _pdl Poundal (force) _buUS American bushel _ph Phot _cal Calorie _pk US peck _cd Candela _psi Pounds per square inch _chain Chain (1 chain = 66 feet or 22 yards) _ptUK UK pint (1 UK gallon=8 UK pints) _cm Centimetre _qt Quart _ct Carat _rad Radian _cu US cup _rd Rad (1 rd=0.01 Gy) _d Day _rem Rem _dB Decibel _rod Rod 1_rod=5.029215842_m _deg Degree (angle) _rpm Revolutions per minute _degreeF Degree Fahrenheit _s Second _dyn Dyne _s second _eV Electron volt _sb Stilb _erg Erg _slug Slug _fath Fathom _sr Steradian _fbm Board foot _st Stere _fc Footcandle (1 footcandle ≈ 10.764 lux) _t Metric ton _fermi Fermi _tbsp Tablespoon _flam Footlambert _tec Tonne of coal equivalent _fm Fathom _tep Tonne of oil equivalent _ft International foot _tex tex=10−6 (kg/m) _ftUS Survey foot _therm EEC therm _g Gram _ton Short ton (1 short ton = 2000 pounds) _ga Standard freefall _tonUK Long (UK) ton _galC Canadian gallon _torr Torr (mmHg) _galUK UK gallon _tr tour=2π rad _galUS US gallon _tsp Teaspoon _gf Gram-force _u Atomic mass unit _gmol Gram-mole _yd International yard _gon Grade _yr Year _grad Grade _µ Micron _grain Grain (1 grain ≈ 0,0648 grams) _µ Micron _h Hour
If a prefix is put before the unit then the unit is multiplied by a power of 10. For example, the prefix k or K, for kilo, indicates multiplication by 103. See table 11.2 for a list of the unit prefixes.
Prefix Name (*10^) n Prefix Name (*10^) n Y yota 24 d deci -1 Z zeta 21 c cent -2 E exa 18 m mili -3 P peta 15 mu micro -6 T tera 12 n nano -9 G giga 9 p pico -12 M mega 6 f femto -15 k or K kilo 3 a atto -18 h or H hecto 2 z zepto -21 D deca 1 y yocto -24
You cannot use a prefix with a built-in unit if the result gives another
built-in unit.
For example:
1_a is one are, but 1_Pa is one pascal and not
10^15_a.
Examples.
10.5 m |
10.5 km |