UNITS

Prefixes • Base SI Units • Derived Units • Conversion Factors

PREFIXES
z a f p n μ m c d
zepto atto fempto pico nano micro milli centi deci
 10-21   10-18   10-15   10-12   10-9   10-6   10-3   10-2   10-1 
 
da h k M G T P E  
deca hecto kilo mega giga tera peta exa  
 101   102   103   106   109   1012   1015   1018   

BASE SI UNITS
QUANTITYSI UNITSYMBOL
Amountmolemol
CurrentampereA
Lengthmetrem
Luminousitycandelacd
Masskilogramkg
TemperaturekelvinK
Timeseconds

DERIVED UNITS
UNIT SYMBOL QUANTITY FORMULA
Bar bar Pressure 0.1 MPa
Becquerel Bq activity (of radionuclides) s-1
Coulomb C electric charge A s
Farad F capacitance C V-1
Gray Gy absorbed dose J kg-1
Hectare ha Area hm2
Henry H inductance Wb A-1
Hertz Hz frequency (periodic) s-1
Joule J energy; work; heat (quantity) N m
Litre l volume dm3
Newton N force kg m s-2
Ohm resistance (electric) V A-1
Pascal Pa pressure; stress N m-2
Stokes St viscosity (kinematic) mm2 s-1
Siemens S conductance A V-1
Tesla T magnetic flux density Wb m-2
Volt V potential difference; emf W A-1
Watt W power J s-1
Weber Wb magnetic flux V s

CONVERSION FACTORS
QUANTITY   STANDARD UNIT   EQUIVALENT TO
Acceleration (Linear) m s-2 2.237 mile hr-1 s-1
3.281 ft s-2
100 galileo
Acceleration (Rotational) rad s-2 0.1592 rev s-2
Activity (of radionuclides) Bq 2.703 x 10-11 curie
Amount (of substance) mol 0.02241 std m3 (0oC, 1 atm)
Angle rad 1/2p circle
0.1592 rev
0.637 quad
57.3 deg
63.66 gon; grade
3.438 x 103 min
2.063 x 105 s
Area m2 1.073 x 10-8 township
3.861 x 10-7 section
1 x 10-4 ha
2.471 x 10-4 acre
1.550 x 103 in2
Capacitance F 8.988 x 1011 statfarad
Conductivity (thermal) W m-1 K-1 2.388 x 10-3 cal cm-1 s-1 K-1
0.5777 Btu ft-1 h-1 oR-1
Current A 2.998 x 109 statampere
Density kg m-3 1.940 x 10-3 slug ft-3
0.06243 lb ft-3
Electric Charge C 2.998 x 109 statcoulomb
Energy J 9.478 x 10-9 therm
3.724 x 10-7 hp h
3.777 x 10-7 kW hr
5.266 x 10-4 Chu
9.478 x 10-4 Btu
9.869 x 10-3 l atm
0.2388 cal
1 x 107 erg
6.242 x 1018 eV
Energy (surface) J m2 1 x 103 erg cm2
Flow (volumetric) m3 s-1 2.119 x 103 ft3 min-1
1.320 x 104 gal(UK) min-1
1.585 x 104 gal(US) min-1
Flux (Magnetic) Wb 7.958 x 106 unit pole
1 x 108 maxwell
Flux (Thermal) W m-2 2.390 x 10-5 cal s-1 cm-2
6.210 x 10-3 lambert
0.3173 Btu h-1 ft-2
Force N 2.248 x 10-4 kip
7.231 pdl
1 x 105 dyne
Frequency (rotational) rad s-1 9.549 rpm
Heat Transfer Coefficient W m-2 K-1 2.390 x 10-5 cal s-1 cm-2 oC-1
4.892 x 10-5 Btu s-1 ft-2 oF-1
Inductance H 1.113 x 10-12 stathenry
Length m 3.243 x 10-17 parsec
1.057 x 10-16 light-year
6.685 x 10-12 astronomical unit
1.799 x 10-4 league (UK)
2.071 x 10-4 league (Statute)
5.400 x 10-4 nautical mile
6.214 x 10-4 mile
4.557 x 10-3 cable
9.113 x 10-3 skein
0.04971 chain
0.1988 perch; pole; rod
0.5468 fathom
1.094 yd
1.312 pace
2.187 cubit
3.281 ft
4.374 span
4.971 link
9.843 hand
39.37 in
221.2 cicero
237.1 pica
472.4 line
2.845 x 103 (didot) point
3.937 x 103 caliber
1 x 1010 Å
Magnetic Flux Density T 1 x 104 G
1 x 109 gamma
Mass kg 9.843 x 10-4 ton (UK)
1.102 x 10-3 ton (US)
0.01968 cwt (UK)
0.02205 cwt (US)
0.06852 slug
2.205 lb
32.15 oz (troy)
35.27 oz (av)
257.2 dram (troy)
564.4 dram (av)
643.0 pennyweight
771.6 scruple
5 x 103 carat
1.543 x 104 grain
Potential Difference V 3.357 x 10-3 statvolt
Power W 2.843 x 10-4 ton of refrigeration
1.360 x 10-3 ch
1.360 x 10-3 hp (metric)
0.7376 ft lb s-1
0.8598 kcal hr-1
3.412 Btu hr-1
Pressure Pa 9.869 x 10-6 atm
1 x 10-5 bar
3.345 x 10-5 mm H2O @ 0oC
1.450 x 10-4 psi
7.5 x 10-3 mm Hg @ 0oC
7.5 x 10-3 torr
Resistance 1.113 x 10-12 statohm
Surface Tension N m-1 1 x 103 dyne cm-1
Temperature K 273 + oC
273 + (oF - 32) / 1.8
273 + (oR - 491) / 1.8
Time s 1.653 x 10-6 week
1.157 x 10-5 day
2.778 x 10-4 hr
0.01667 min
1 x 108 shake
Velocity (Linear) m s-1 3.021 x 10-3 mach
1.946 knot
2.237 mph
3.281 ft s-1
Velocity (Rotational) rad s-1 9.551 rev min-1
57.3 deg s-1
Viscosity cP 6.720 x 10-4 lb ft-1 s-1
1 x 10-3 Pa s
Viscosity (Kinematic) cSt 1 x 10-6 m2 s-1
1.560 x 10-3 in2 s-1
Volume m3 0.2759 cord
1 stere
4.193 hogshead (US)
6.290 barrel (Oil)
28.38 bushel (US)
35.31 ft3
113.5 peck (US)
220 gal (UK)
264.2 gal (US)
1 x 103 l
1.057 x 103 quart
1.760 x 103 pint (UK)
2.113 x 103 pint (US)
4.227 x 103 cup
7.039 x 103 gill (UK)
8.454 x 103 gill (US)
3.520 x 104 fl oz (UK)
6.763 x 104 tbsp
2.029 x 105 tsp
1.200 x 107 drop

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