Table 1. SI base units

SI base unit Base quantity Name Symbol length meter m mass kilogram kg time second s electric current ampere A thermodynamic temperature kelvin K amount of substance mole mol luminous intensity candela cd

Table 2.  Examples of SI derived units

SI derived unit Derived quantity Name Symbol area square meter m2 volume cubic meter m3 speed,velocity meter per second m/s acceleration meter per second squared m/s2 wave number reciprocal meter m-1 mass density kilogram per cubic meter kg/m3 specific volume cubic meter per kilogram m3/kg current density ampere per square meter A/m2 magnetic field strength ampere per meter A/m amount-of-substance concentration mole per cubic meter mol/m3 luminance candela per square meter cd/m2 mass fraction kilogram per kilogram,which may be represented by the number 1 kg/kg = 1

Table 3. SI derived units with special names and symbols

SI derived unit Derived quantity Name Symbol Expression in terms of other SI units Expression in terms of SI base units plane angle radian (a) rad - m·m-1 = 1 (b) solid angle steradian (a) sr(c) - m2·m-2 =1 (b) frequency hertz Hz - s-1 force newton N - m·kg·s-2 pressure,stress pascal Pa N/m2 m-1 ·kg·s-2 energy, work, quantity of heat joule J N·m m2 ·kg·s-2 power,radiant flux watt W J/s m2 ·kg·s-3 electric charge, quantity of electricity coulomb C - s·A electric potential difference,electromotive force volt V W/A m2 ·kg·s-3·A-1 capacitance farad F C/V m-2·kg-1·s4·A2 electric resistance ohm Ω V/A m2·kg·s-3·A-2 electric conductance siemens S A/V m-2·kg-1·s3·A2 magnetic flux weber Wb V·s m2·kg·s-2·A-1 magnetic flux density tesla T Wb/m2 kg·s-2·A-1 inductance henry H Wb/A m2·kg·s-2·A-2 Celsius temperature degree Celsius °C - K luminous flux lumen lm cd·sr (c) m2·m-2·cd = cd illuminance lux lx lm/m2 m2·m-4·cd = m-2·cd activity (of a radionuclide) becquerel Bq   - s-1 absorbed dose, specific energy (imparted), kerma gray Gy J/kg m2·s-2 dose equivalent (d) sievert Sv J/kg m2·s-2

Table 4.  Examples of SI derived units whose names and symbols include SI derived units with special names and symbols

SI derived unit Derived quantity Name Symbol dynamic viscosity pascal second Pa·s moment of force newton meter N·m surface tension newton per meter N/m angular velocity radian per second rad/s angular acceleration radian per second squared rad/s2 heat flux density, irradiance watt per square meter W/m2 heat capacity, entropy joule per kelvin J/K specific heat capacity,specific entropy joule per kilogram kelvin J/(kg·K) specific energy joule per kilogram J/kg thermal conductivity watt per meter kelvin W/(m·K) energy density joule per cubic meter J/m3 electric field strength volt per meter V/m electric charge density coulomb per cubic meter C/m3 electric flux density coulomb per square meter C/m2 permittivity farad per meter F/m permeability henry per meter H/m molar energy joule per mole J/mol molar entropy, molar heat capacity joule per mole kelvin J/(mol·K) exposure(x and γ rays) coulomb per kilogram C/kg absorbed dose rate gray per second Gy/s radiant intensity watt per steradian W/sr radiance watt per square meter steradian W/(m2·sr)

Table 5. SI Prefixes

10의 승수 Prefix 우리말 Symbol 18 exa 엑사 E 15 peta 페타 P 12 tera 테라 T 9 giga 기가 G 6 mega 메가 M 3 kilo 킬로 k 2 hecto 헥토 h 1 deca 데카 da 0 basic unit 기본단위 - -1 deci 데시 d -2 centi 센티 c -3 milli 밀리 m -6 micro 마이크로 μ -9 nano 나노 n -12 pico 피코 p -15 femto 펨토 f -18 atto 아토 a

Table6. 단위환산표

MULTIPLY BY TO GET MULTIPLY BY TO GET Acres 43,560 Sq. Feet Gilberts 0.7958 Ampere Turns Acres 0.40469 Hectares Hectares 1.0764×E-5 Sq. Feet Angstrom E-8 Centimeters Horse-Power 0.7457 Kilowatts Atmospheres 760 mm of Mercury Horse-Power Hours 2.684×E6 Joules Atmospheres 33.90 Feet of Water Inches 2.54 Centimeters BTU 1055 Joules Inches of Water 5.204 Pounds/Sq.Foot BTU 0.2930 Watts Joules 9.480×E-4 BTU Cubic Feet 7.481 Gallons(US) Joules 2.778×E-4 Watt-Hours Cubic Feet 6.229 Gallons(Br.) Kilograms< 2.205 Pounds Cubic Feet 28.316 Liters Kilogram-Calories 3.968 BTU Dynes 1.020×E-3 Grams Kilogram-Calories 1.163×E-3 Kilowatt-Hours Ergs 9.4805×E-11 BTU Kilometers 0.6214 Miles Foot-Pounds 1.356 Joules Knots 1.152 Miles/Hour Foot-Pounds 3.766×E-7 KiloWatt Hours Lines/Sq.Cm. 1 Gausses Gallons 0.1337 Cubic Feet Liters 61.02 Cubic Inches Gallons 3.7853 Liters Lux 0.0929 Foot Candles Grams 0.03527 Ounces Meters 39.37 Inches Microns 0.001 Millimeters Square Feet 2.296×E-5 Acres Miles 1609 Meters Square Inches 1.273×E6 Circular Mils Miles 5280 Feet Square Yard 0.836127 Sq. Meters Ounces 28.35 Grams Ton(Long) 2240 Pounds Ounces(Fluid) 29.57 Cu. Cm. Watts 0.05688 BTU/Min. Pounds 453.6 Grams Watt Hours 3.413 BTU Quart (US dry) 1.10119 Liters Webers 10 Maxwells Quart(US Fl.) 0.946326 Liters Yards 0.914402 Meters