Units Topics
- A
- The abbreviation of Ampere, the SI unit of Electric current.
- A
- The Ångström is an old unit used for measuring the wavelength of electromagnetic radiation including visible light and X-rays.
- aA
- Abbreviation of abampere.
- ab
- A prefix indicating that an electrical unit is part of the CGS absolute electromagnetic system.
- Abampere
- The CGS electromagnetic unit of current equal to 10 Amperes.
- Abcoulomb
- The CGS unit of electric charge equal to 10 Coulomb.
- Abfarad
- The CGS unit of capacitance equal to 1.0x109Farad.
- Abhenry
- The CGS unit of inductance equal to 1.0x10-9Henry.
- Abmho
- The CGS unit that is the reciprocal of the ohm equal to 1.0x109Siemens.
- Abohm
- The CGS unit of electrical resistance equal to 1.0x10-9Ohms.
- abtesla
- The CGS unit of magnetic flux density equal to 10-4 tesla.
- Abvolt
- The CGS unit of electromotive force equal to 1.0x10-9Volt.
- abwatt
- The CGS unit of power equal to 10-7 watt.
- abweber
- The CGS unit of magnetic flux equal to 10-8 weber. Also known as the maxwell.
- ac ft
- Abbreviation of acre foot, a volume one foot deep covering an area of one acre.
- Acoustic Ohm
- The unit of acoustic impedance.
- Acre
- A British unit of area, traditionally used in agriculture.
- Acre Foot
- A volume one foot deep covering an area of one acre.
- Acre Inch
- A volume one inch deep covering an area of one acre.
- Aeon
- In astronomical terms, 1,000 million years.
- Ah
- Abbreviation of ampere-hour.
- amp
- The informal name for Ampere.
- Ampere
- The SI unit of Electric current.
- Ampere-Hour
- An alternative unit of electrical charge.
- AMU
- Defined as one twelfth of the mass of the most abundant isotope of carbon (12C)
- Apothecaries Ounce
- Once used as a measurement of weight for drugs and other medical substances.
- Are
- A derived SI Unit of area. 1 Are = 100m2
- Area
- The derived SI unit of area is the m2.
- Areal Weight
- The weight of fibre per unit area, width times length, of tape or fabric.
- at
- Abbreviation for Technical Atmosphere.
- atm
- An abbreviation of atmosphere.
- Attometre
- A distance of 10-18m.
- bar
- A derived unit of pressure used in meteorology. 1 bar = 1x105 Pa.
- Barn
- A unit of nuclear cross section, 1 Barn = 10-28m2.
- Barye
- The CGS unit of pressure, equal to 1 dyne per square centimetre.
- Becquerel
- The Becquerel is a unit used to measure a radioactivity. One Becquerel is that quantity of a radioactive material that will have 1 transformations in one second.
- Board Foot
- A unit of lumber volume, a rectangular solid nominally 12" x 12" x 1". The equivalent of a board 1-foot square and 1 inch thick.
- British Thermal Unit
- The amount of heat required to raise the temperature of 1 pound of water by 1° Fahrenheit.
- Btu
- Abbreviation of British Thermal Unit.
- Btu h-1
- An abbreviation of British thermal units per hour, the unit of heat flow rate in the British system of units.
- C
- An abbreviation of coulomb, the quantity of charge which passes any section of a conductor in one second when a current of one ampere is flowing.
- Cable Length
- Originally the length of a ship′s anchor cable, 120 fathoms.
- cal
- An abbreviation of calorie, a unit of energy in the British system of units.
- Calendar Year
- 1 calendar year = 31.536x106 seconds
- Calorie
- A unit of energy in the British system of units. Still used to define the amount of energy amount of energy contained in foods.
- Calorie per Second
- Unit of power.
- Calorific Value
- The ratio of energy to volume measured in joules per cubic metre.
- Candela
- The SI unit of luminous intensity.
- cc
- Abbreviation of Cubic Centimetre.
- cd
- An abbreviation of candela, the SI unit of luminous intensity.
- Celsius Temperature Scale
- The centigrade scale of temperature was defined as 0°C at the ice point of water and as 100°C at the boiling point of water (at 1 standard atmosphere).
- Centigrade
- The centigrade scale of temperature was defined as 0°C at the ice point of water and as 100°C at the boiling point of water (at 1 standard atmosphere).
- Centigrade Heat Unit
- The amount of heat necessary to raise one pound weight of water through 1° C.
- Centimetre
- The centimetre is a unit of length and is one hundredth of a metre by definition.
- Centimetre Gramme Second
- A system of units in which the fundamental units are centimetre, gramme and second.
- centipoise
- One hundredth of a poise, the CGS derived unit of dynamic viscosity of a fluid.
- CGS Units
- Abbreviation for centimetre-gramme-second.
- Chu
- Abbreviation of centigrade heat unit.
- Circular Mil Foot
- A unit of volume of a conductor having a cross-sectional area of 1 circular mil and a length of 1 foot.
- cm
- The centimetre is a unit of length and is one hundredth of a metre by definition.
- Collision Density
- The rate at which collisions are occurring per unit volume per unit time.
- Coulomb
- Defined as the quantity of charge which passes any section of a conductor in one second when a current of one ampere is flowing.
- cP
- An abbreviation of centipoise, one hundredth of a poise. The CGS derived unit of dynamic viscosity of a fluid.
- CPS
- Abbreviation of cycles per second.
- Cross Sectional Area
- The area of a slice of an object.
- Cubic Centimetre
- Abbreviated as cm3 or cc.
- Cubic Foot
- 1 cubic foot = 0.0283168 m3
- Cubic Foot per Minute
- British imperial unit of flow rate.
- Cubic Foot per Second
- British imperial unit of flow rate.
- Cubic Inch
- The cubic inch has traditionally been used in American to define the swept volume of internal combustion engines.
- Cubic Metre
- SI unit of volume.
- Cubic Yard
- 1 cubic yard = 0.764555 m3
- Cubit
- Unit of length equal to 457.2x10-3m.
- cufm
- Cubic foot per minute, a British imperial unit of flow rate.
- cusec
- Abbreviation of cubic foot per second.
- cwt
- Abbreviation of hundredweight, this is an imperial unit of mass.
- dalton
- The atomic mass unit is sometimes called the dalton, after John Dalton.
- Debye
- Unit of dipole moment.
- decametre
- Abbreviated as dam, unit length equal to 10m.
- Decibel
- The human ear responds logarithmically and it is convenient to deal in logarithmic units in audio systems.
- decimetre
- Abbreviated as dm, unit length equal to 10-1m.
- Denier
- A unit used in measuring the thickness (fineness) of yarn. It is the mass in grams of 9000m of yarn.
- Dots Per Inch
- A unit used to measure the resolution, or sharpness of an image.
- Dyne
- A force of 1 dyne acting on a mass of 1g imparts an acceleration of 1cms-2.
- Earth Rate Unit
- Unit of angular velocity equal to 15° per hour.
- Eon
- In astronomical terms, 1,000 million years.
- Erg
- Unit of energy equal to 100.0x10-9J.
- ERU
- Unit of angular velocity equal to 15° per hour.
- F
- An abbreviation of farad, the SI unit of capacitance.
- Fahrenheit
- On the Fahrenheit scale 0°C = 32°F and 100°C = 212°F
- Farad
- The SI unit of capacitance.
- Faraday
- Quantity of electrical charge associated with one mole of chemical charge equal to 96485.3C
- Faraday Constant
- F = 9.648456x104 Cmol-1
- fc
- Abbreviation of Foot Candle.
- Feet
- The plural of foot. One foot was defined as one third of the Imperial Standard yard. The abbreviation of foot is ft
- Feet per Minute
- Old imperial units of velocity, abbreviated as fpm or ft min-1.
- Feet per Second Squared
- Old imperial unit of acceleration.
- Femtometre
- Abbreviated as fm, unit of distance equal to 10-15m.
- Fermi
- A derived SI Unit of length equal to 10-15m
- Fluid Ounce
- 20 fluid ounces = 1 pint
- Foot
- One foot was defined as one third of the Imperial Standard yard.
- Foot Candle
- A measure of light intensity on a surface being illuminated.
- Foot Pound
- Imperial unit of mechanical energy.
- ft
- One foot was defined as one third of the Imperial Standard yard. The abbreviation of foot is ft
- ft lb
- Abbreviation of foot pound, Imperial unit of mechanical energy.
- ft min-1
- Abbreviation of Feet per Minute.
- ft2
- Imperial unit of area.
- ft3
- Cubic foot.
- ft3s-1
- Cubic foot per second.
- ft s-2
- Abbreviation of Feet per Second Squared, an old imperial unit of acceleration.
- Gallon
- This unit of volume is defined in the British and American system of units. Note 1 UK gallon = 1.2 US gallons.
- Gallons per Minute
- Volume flow rate.
- Giga electron Volt
- One billion electron Volts.
- Gigahertz
- 109 cycles per second.
- GPM
- Abbreviation of Gallons per Minute.
- gram
- The CGS unit of mass equal to 10-3kg.
- gramme
- Older spelling of gram, the CGS unit of mass equal to 10-3kg.
- Hectare
- An SI derived unit of area.
- Inches
- A secondary unit in the British system of units, now replaced by the SI system and the metre.
- Joule
- The SI unit of energy.
- kilo calories
- 1000 calories.
- kilo electron volts
- Abbreviated as keV, one thousand electron volts.
- kilo pounds per square inch
- A unit of pressure used in the imperial system of units.
- Kilogram
- The SI unit of mass is the kilogram.
- Kilogram Force
- Equivalent to the force exerted by 1 kilogram due to the local acceleration due to gravity.
- kilojoule
- One thousand joules.
- kilometre
- A length equal to 1000 metres.
- Kilometres Per Hour
- Unit of velocity used by most land based vehicles.
- kilowatt
- One thousand watts.
- kiloWatt hour
- Unit of energy equal to 3.6x106J.
- km
- Abbreviation of kilometre.
- kWh
- Abbreviation of kiloWatt hour.
- lbf ft
- An abbreviation of pound-force foot, the unit of torque in the old British system of units.
- Leap Year
- Leap years are years with 366 days, instead of the usual 365.
- Megahertz
- 1000000Hz.
- Megawatt
- One million watts.
- Metre
- The metre is the SI unit of length.
- Metric Ounce
- A unit of mass, equal to 25 grams. Also known as a mounce.
- microampere
- One millionth of an ampere.
- microbar
- A unit of pressure equal to one millionth of a bar.
- Micrometre
- One-millionth of a metre.
- microvolt
- One millionth of a volt.
- millimetre
- milli is the prefix representing a multiplication of 10-3 and metre is the SI unit of length.
- millivolt
- A unit of electrical potential equal to one thousandth of a volt.
- milliwatt
- Unit of power equal to 0.001 watt.
- mounce
- A unit of mass, equal to 25 grams.
- nanoampere
- One billionth of an ampere.
- Nanometre
- Abbreviated as nm, unit of length equal to 10-9 metres, and equal to 10 Å (Angstroms).
- Nanosecond
- One billionth of a second, 10-9 s.
- nanovolt
- One billionth of a volt.
- Newton
- The SI unit of force.
- Newton Metre
- The SI unit of Torque.
- nm
- Abbreviation of nanometer as nm, unit of length equal to 10-9 metres, and equal to 10 Å (Angstroms).
- Nm
- Abbreviation of newton metre, the SI unit of Torque.
- ns
- Abbreviation of nanosecond, 10-9 s.
- Ounce Force
- A derived unit of force in the British system of units.
- Ounces
- A secondary unit in the British system of units. 1 ounce (oz) = 28.34952 g
- Pa
- The SI derived unit of pressure is the pascal.
- picogram
- A mass equal to 10-12g.
- picometre
- A distance equal to 10-12 metres.
- Poise
- Named after the physicist Poiseuille this is the CGS derived unit of dynamic viscosity.
- Pound Force Foot
- The unit of torque in the old British system of units, abbreviated lbf ft.
- Pounds per Square Inch
- A British imperial unit of pressure. 1.0 psi = 6894.757 Pa
- Sidereal Year
- 1 sidereal year = 31.55815x106 seconds
- Slinch
- Equal to 12 slugs, an old unit of mass.
- Square Feet
- Imperial unit of area.
- Statampere
- The unit ofcurrent in the obsolete electrostatic system of units.
- Statcoulomb
- The unit of charge in the obsolete electrostatic system of units.
- Statfarad
- The unit of capacitance in the obsolete electrostatic system of units.
- Statvolt
- The unit of electromotive force in the obsolete electrostatic system of units.
- Statwatt
- The unit of power in the obsolete electrostatic system of units.
- Tera Electron Volt
- One trillion electron Volts.
- Terahertz
- One trillion cycles per second, 1012 Hz.
- Thousandths of an Inch
- Often abbreviated as thou. A unit of length used by engineers.
- THz
- Abbreviation of terahertz, 1012 Hz.
- Tons per Square Inch
- Old imperial unit of pressure, abbreviated as Tsi or tonf in-2.
- Tropical Year
- 1 tropical year = 31.55693x106 seconds
- Troy Ounce
- An old British unit of mass mainly used for measuring prescious metals. 1 troy ounce = 31.1035 g
- Unit of Blood
- Unit of volume for human blood and its components.
- Units Books
- Lists all Units Books in the Encyclopaedia
- Units Calculations
- Lists all Units Calculations in the Encyclopaedia
- Units Conversions
- Lists all Units Conversions in the Encyclopaedia
- Units Weblinks
- Lists all Units Weblinks in the Encyclopaedia
- Volt
- The volt is the SI unit of electromotive force.
- Volt Amperes Reactive
- Unit used to measure reactive power in an AC electric power system.
- Volt-Ampere
- The amount of apparent power in an electrical circuit, equal to the product of voltage and current.
- Voltampere (VA)
- The product of rms voltage and rms current in an electronic circuit. It is the unit of apparent power in the International System of Units (SI).
- Volume
- There are a number of derived units of volume in the British system of units and the SI system of units.
- Watt
- The watt is the SI unit of power and is equal to 1 joule per second.
- Watt Hour
- A unit of energy equivalent to one watt of power expended for one hour of time.
- Watt Hour Meter
- A meter used to measure electrical energy.
- Watt Hours per Kilogram
- Unit of energy density.
- Weber
- The weber is the SI unit of magnetic flux.
- Winchester Gallon
- The US gallon, equivalent to 3.785411784 litres.
- Yard
- The yard was a unit of length of the British system of units.
- yd
- An abbreviation of yard, a standard unit of length of the British system of units.
- Year
- 1 calendar year = 31.536x106 seconds
Subjects: Biology Chemistry Mechanical Engineering Physics