This web page attempts to do something many other web sites fail to do and that
is to be precise. By that, I mean I give you a rational fraction definition of
a conversion factor rather than a rounded decimal fraction. For example, the US
survey foot is normally given as 304.8006 mm when it is actually 12*1000/39.37
mm =~ 304.80060,96012,19202,43840,48768,09753,61950,72390,14478.. etc. mm.
If you wish to convert one unit of measure to another, multiply by one factor
and divide by the other. For example, to convert bolt of cloth to cubits,
bolt of cloth = 36.576 m
cubit = 457.2 mm
multiply by 36.576 m and divide by 457.2 mm. So, one bolt of cloth =
(1000*36.576)/ 457.2 = 80 cubits.
The current standard metric system is the International System of Units or SI.
It is based on the meter, kilogram, second, Kelvin, Ampere, candela, and mole.
The seven SI base units are for length, mass, time, temperature, electric
current, luminous intensity and amount of substance. SI also has derived units
defined in terms of the seven base units. All other quantities like work, force,
and power are defined in terms of SI derived units.
================================================================================
Units of Length (SI meter m)
One Definition Equivalent to SI units
----------------- --------------- --------------------- = ----------------------
angstrom 10^-10 m 1/10^10 = 1.0e-10 m
angstrom 10^-10 m 1/10 = 0.1 nm
astronomical unit A 2997,92458.0 * 499.00478,63852 =~ 14,95978,71464.184 m
bolt of cloth 120 ft 25.4*12*120/1000 = 36.576 m
cable length USN 120 fathoms 25.4*12*720/1000 = 219.456 m
caliber cal 1/100 in 25.4/100 = 0.254 mm
centimeter cm 10^-2 m 10 = 10.0 mm
chain Gunter's 4 rods = 66 ft 25.4*12*66/1000 = 20.1168 m
chain Ramden's 100 ft 25.4*12/10 = 30.48 m
cubit 18 in 25.4*18 = 457.2 mm
decimeter dm 10^-1 m 100 = 100.0 mm
dekameter dam 10 m 10 = 10.0 m
ell 45 in 25.4*45/1000 = 1.143 m
fathom 6 ft 25.4*12*6/1000 = 1.8288 m
foot ft 12 in 25.4*12 = 304.8 mm
foot US survey 12 in USs 12*1000/39.37 =~ 304.80060,96012,19 mm
furlong furl 40 rods=660 ft 25.4*12*660/1000 = 201.168 m
gigameter Gm 10^9 m 10^9 = 1.0e9 m
hand 4 in 25.4*4 = 101.6 mm
hectometer 100 meters 100 = 100.0 m
inch in 25.4 mm 25.4 = 25.4 mm
inch Eng old 914.3992/36 = 25.3999777... mm
inch US old 1000/39.37 mm 1000/39.37 =~ 25.40005,08001,02 mm
inch US survey 1000/39.37 mm 1000/39.37 =~ 25.40005,08001,02 mm
kilometer km 1000 m 1000 = 1000.0 m
league naut Brit 18240 ft 25.4*12*18240/10^6 = 5.55955,2 km
league naut Int 5556 m 5556/1000 = 5.556 km
league statute 3 statute miles 25.4*12*3*5280/10^6 = 4.82803,2 km
light year ly 315,56925.9747*2997,92458 = 9,46052,84048,79358.8126 m
ligne Paris 2.2558291 mm 2.2558291 = 2.25582,91 mm
line button 1/40 in 25.4/40 = 0.635 mm
line Brit 1/12 in 25.4/12 = 2.11666... mm
link Gunter's 1/100 chain G 25.4*12*66/100 = 201.168 mm
link Ramden's 1/100 chain R 25.4*12 = 304.8 mm
meter m See meter: 1 = 1.0 m
micrometer um 10^-6 m 1 = 1.0 um
micron 10^-6 m 1 = 1.0 um
mil 10^-3 in 25.4 = 25.4 um
mile naut Brit 6080 ft 25.4*12*6080/10^6 = 1.85318,4 km
mile naut Int 1852 m 1.852 = 1.852 km
mile statute mi 8 furl=5280 ft 25.4*12*5280/10^6 = 1.60934,4 km
millimeter mm 10^-3 m 1 = 1.0 mm
millimicron 10^-9 m = 1 nm 1 = 1.0 nm
nanometer nm 10^-9 m 1 = 1.0 nm
pace US 2.5 ft = 30 in 25.4*30 = 762.0 mm
palm 3 in 25.4*3 = 76.2 mm
parsec distance of parallax of 1 arc second =~ 30.85677,59725e15 m
perch = rod 16.5 ft 25.4*198/1000 = 5.0292 m
pica printer 12 points pr 25.4*0.166044 = 4.21751,76 mm
pica computer 12 points comp 25.4/6 = 4.2333... mm
point printer 0.013837 in 25.4*0.013837 = 0.35145,98 mm
point computer 1/72 in 25.4/72 = 0.35277,7... mm
pole = rod 16.5 ft 25.4*198/1000 = 5.0292 m
rod 16.5 ft 25.4*198/1000 = 5.0292 m
rope Brit 20 ft 25.4*12*20/1000 = 6.096 m
size watch US 1 36/30 in 25.4*36/30 = 30.48 mm
size watch US d 1/30 in 25.4/30 = 0.84666... mm
skein US 360 ft 25.4*12*360/1000 = 109.728 m
span 9 in 25.4*9 = 228.6 mm
yard 3 ft 25.4*3*12 = 914.4 mm
yard Eng old 914.3992 = 914.3992 mm
yard US old 1000*36/39.37 =~ 914.40182,88036,58 mm
================================================================================
Units of Area (SI Sq. meter m^2)
One Definition Equivalent to SI units
----------------- --------------- --------------------- = ----------------------
acre Int 43560 sq ft 43560*(0.0254*12)^2 = 4046.85642,24 m^2
acre US survey 43560 sq ft USs 43560*(12/39.37)^2 =~4046.87260,98742,5 m^2
are (10 meters)^2 100 = 100.0 m^2
barn 10^-24 sq cm 10^-28 = 1.0e-28 m^2
centare 1 m^2 1 = 1.0 m^2
circular inch circular inch: pi*(25.4)^2 / 4 =~ 506.70747,90975 mm^2
circular mil circular mil: pi (25.4)^2 / 4 =~ 506.70747,90975 um^2
circular mm circular mm: pi / 4 =~ 0.78539,81634 mm^2
hectare (100 meters)^2 10000 =10000.0 m^2
rood Brit 40 square rods 40*(25.4*198/1000)^2 = 1011.71410,56 m^2
sq chain G (chain G)^2 (25.4*12*66/1000)^2 = 404.68564,224 m^2
sq chain R (chain R)^2 (25.4*12/10)^2 = 929.0304 m^2
sq cm (10 mm)^2 100 = 100.0 mm^2
sq decimeter decimeter^2 100^2 =10000.0 mm^2
sq dekameter dekameter^2 10^2 = 100.0 m^2
sq ft ft^2 (0.0254*12)^2 = 0.09290,304 m^2
sq ft US survey (ft USs)^2 (12*1000/39.37)^2 =~ 0.09290,34116,1 m^2
sq hectometer hectometer^2 100^2 =10000.0 m^2
sq in in^2 25.4^2 = 645.16 mm^2
sq km (1000 m)^2 1 = 1.0 km^2
sq links G (links G)^2 (25.4*12*66/100)^2 =40468.56422,4 mm^2
sq links R (links R)^2 (25.4*12)^2 =92903.04 mm^2
sq meter meter^2 1 = 1.0 m^2
sq mil mil^2 25.4^2 = 645.16 um^2
sq mile mile^2 (25.4*12*5280/10^6)^2 = 2.58998,81103,36 km^2
sq millimeter millimeter^2 1 = 1.0 mm^2
sq rod rod^2 (25.4*198/1000)^2 = 25.29285,264 m^2
sq yard yard^2 (25.4*3*12/1000)^2 = 0.83612,736 m^2
township US (6 miles)^2 (6*25.4*12*5280/10^6)^2 = 93.23957,19720,96 km^2
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Units of Volume (SI cu meter m^3)
One Definition Equivalent to SI units
----------------- --------------- --------------------- = ----------------------
acre-foot 43560 cu ft 43560*(0.0254*12)^3 = 1233.48183,75475,2 m^3
acre-foot survey 43560 cu ft USs 43560*(12/39.37)^3 =~1233.48923,84681,5 m^3
acre-inch 43560/12 cu ft 43560*(0.0254*12)^3/12= 102.79015,31289,6 m^3
acre-inch survey 3630 cu ft USs 3630*(12/39.37)^3 =~ 102.79076,98723,5 m^3
bag Brit liq 24 gallons 24*4.54609/1000 = 0.10910,616 m^3
barrel Brit liq 36 gallons 36*4.54609/1000 = 0.16365,924 m^3
barrel US dry 7056 cu in 7056*0.0254^3 = 0.11562,71235,84 m^3
barrel US liq 31.5 gal US liq 31.5*231*0.0254^3 = 0.11924,04711,96 m^3
barrel US petro 42 gal US liq 42*231*0.0254^3 = 0.15898,72949,28 m^3
board foot 144 cu in 144*2.54^3 = 2359.73721,6 cc
bucket Brit liq 4 gal Imp liq 4*4.54609/1000 = 0.01818,436 m^3
bushel Brit liq 8 gal Imp liq 8*4.54609/1000 = 0.03636,872 m^3
bushel US ah 2747.715 cu in 2747.715*0.0254^3 = 0.04502,69815,5876 m^3
bushel US dry 2150.42 cu in 2150.42*0.0254^3 = 0.03523,90701,6688 m^3
bushel US heaped 2688.025 cu in 2688.025*0.0254^3 = 0.04404,88377,086 m^3
butt Brit wine 126 gal US liq 126*231*0.0254^3 = 0.47696,18847,84 m^3
centiliter 1/100 L 10 = 10.0 cc
cord 128 cu ft 128*(0.0254*12)^3 = 3.62455,63637,76 m^3
cord foot 16 cu ft 16*(0.0254*12)^3 = 0.45306,95454,72 m^3
cu cm = cc = cm^3 (m/100)^3 1/1000000 = 0.00000,1 m^3
cu decimeter (m/10)^3 1000 = 1000.0 cc
cu dekameter (10 m)^3 1000 = 1000.0 m^3
cu foot (1 foot)^3 (0.0254*12)^3 = 0.02831,68465,92 m^3
cu in (1 inch)^3 2.54^3 = 16.38706,4 cc
cu meter (1 meter)^3 1 = 1.0 m^3
cu mm = mm^3 (m/1000)^3 1/10^3 = 0.001 cc
cu yard (1 yard)^3 (0.0254*36)^3 = 0.76455,48579,84 m^3
cup 8 ounces USl 231*2.54^3/16 = 236.58823,65 cc
decistere m^3 / 10 1/10 = 0.1 m^3
dekaliter 10 L 1/100 = 0.01 m^3
drachm Brit liq gal Bl/8/160 1000*4.54609/8/160 = 3.55163,28125 cc
dram Brit liq 1/8 ounce Bl 1000*4.54609/8/160 = 3.55163,28125 cc
dram US liq 1/8 oz 231*2.54^3/1024 = 3.69669,11953,125 cc
firkin Brit liq 1/4 barrel Bl 9*4.54609/1000 = 0.04091,481 m^3
firkin US liq 1/4 barrel USl 31.5*231*0.0254^3/4 = 0.02981,01177,99 m^3
gallon Imp liq 4.54609 L 1000*4.54609 = 4546.09 cc
gallon US dry 1/8 bushel 2150.42*2.54^3/8 = 4404.88377,086 cc
gallon US liq 231 cu in 231*2.54^3 = 3785.41178,4 cc
gill Brit liq 5 ounces Bl 1000*4.54609/32 = 142.06531,25 cc
gill US liq 4 ounces USl 231*2.54^3/32 = 118.29411,825 cc
hectoliter 100 L 1/10 = 0.1 m^3
hogshead old Eng 63 gal US liq 63*231*0.0254^3 = 0.23848,09423,92 m^3
hogshead Bl 52.5 gal Bl 52.5*1000*4.54609 = 0.23866,9725 m^3
kilderkin Brit 1/2 barrel Bl 18*4.54609/1000 = 0.08182,962 m^3
kiloliter 1000 L 1 = 1.0 m^3
last Brit 80 bushels Bl 640*4.54609/1000 = 2.90949,76 m^3
liter L cu decimeter 1000 = 1000.0 cc
milliliter mL liter / 1000 1 = 1.0 cc
minim Brit 1/60 dram Bl 1000*4.54609/76800 =~0.059193,88020,8333 cc
minim US 1/60 dram USl 231*2.54^3/61440 = 0.06161,15199,21875 cc
noggin Brit 1/4 pint Bl 1000*4.54609/32 = 142.06531,25 cc
ounce Brit liq gal Bl/160 1000*4.54609/160 = 28.41306,25 cc
ounce US liq oz gal US liq/128 231*2.54^3/128 = 29.57352,95625 cc
peck Brit 2 gal Brit liq 2*1000*4.54609 = 9092.18 cc
peck US bushel US dry/4 2150.42*2.54^3/4 = 8809.76754,172 cc
perch masonry 24.75 cu ft 24.75*(12*0.0254)^3 = 0.70084,19531,52 m^3
pint Brit liq 1/8 gal Bl 1000*4.54609/8 = 568.26125 cc
pint US dry bushel US dry/64 2150.42*2.54^3/64 = 550.61047,13575 cc
pint US liq 1/8 gal US liq 231*2.54^3/8 = 473.17647,3 cc
pottle Brit liq 1/2 gal Bl 1000*4.54609/2 = 2273.045 cc
puncheon Brit 70 gal Imp liq 70*4.54609/1000 = 0.31822,63 m^3
puncheon US 84 gal US liq 84*231*0.0254^3 = 0.31797,45898,56 m^3
quart Brit 1/4 gal Bl 1000*4.54609/4 = 1136.5225 cc
quart US dry 2 pints US dry 2150.42*2.54^3/32 = 1101.22094,2715 cc
quart US liq 32 oz US liq 231*2.54^3/4 = 946.35294,6 cc
quartern Bd 1/4 peck Brit 1000*4.54609/2 = 2273.045 cc
quartern Bl 1/4 pint Bl 1000*4.54609/32 = 142.06531,25 cc
quartern USl 1/4 pint USl 231*2.54^3/32 = 118.29411,825 cc
register ton 100 cu ft 100*(12*0.0254)^3 = 2.83168,46592 m^3
scruple Brit liq 20 minims Brit 1000*4.54609/3840 =~ 1.18387,76041,6667 cc
seam Brit 8 bushels Bl 64*4.54609/1000 = 0.29094,976 m^3
stere 1 cu meter 1 = 1.0 m^3
tablespoon US 1/2 oz 231*2.54^3/256 = 14.78676,47812,5 cc
tablespoon metric 15 ml 15 = 15.0 cc
teaspoon US 1/3 tablespoon 231*2.54^3/256/3 = 4.92892,15937,5 cc
teaspoon metric 5 ml 5 = 5.0 cc
tun 252 gal US liq 252*231*0.0254^3 = 0.95392,37695,68 m^3
================================================================================
Units of Mass (SI kilogram kg)
One Definition Equivalent to SI units
----------------- --------------- --------------------- = ----------------------
carat (metric) 2/10 g 2/10 = 0.2 g
carat 1877 (old) 3.168 grains 3.168*453.59237/7000 = 0.20528,29468,8 g
cental 100 lb 100*453.59237/1000 = 45.35923,7 kg
centigram cg 1/100 g 1/100 = 0.01 g
centner 100 kg 100 = 100.0 kg
dalton Da see dalton: 1/NA =~ 1.660538728e-24 g
dram avdp 1/256 lb 453.59237/256 = 1.77184,51953,125 g
dram troy 60 grains 60*453.59237/7000 = 3.88793,46 g
grain 1/7000 lb 453.59237/7000 = 0.06479,891 g
gram 1/1000 kg 1.0 = 1.0 g
gramma 1 microgram 1/1000000 = 0.00000,1 g
hectograms 100 g 100 = 100.0 g
hundredwgt long 112 lb 112*453.59237/1000 = 50.80234,544 kg
hundredwgt short 100 lb 100*453.59237/1000 = 45.35923,7 kg
kilogram kg mass of international prototype of kg = 1000.0 g
microgram ug 10^-6 g 1/1000000 = 0.00000,1 g
milligram mg 10^-3 g 1/1000 = 0.001 g
myriagram one ten thousandth of a centner = 10.0 g
ounce avdp 1/16 lb 453.59237/16 = 28.34952,3125 g
ounce troy 20 dwt 480*453.59237/7000 = 31.10347,68 g
pennyweight dwt 24 grains 24*453.59237/7000 = 1.55517,384 g
pound avdp lb 453.59237 g 453.59237 = 453.59237 g
pound troy 12 troy oz. 5760*453.59237/7000 = 373.24172,16 g
quarter Brit 28 lb 28*453.59237/1000 = 12.70058,636 kg
quarter US long 560 lb 560*453.59237/1000 = 254.01172,72 kg
quarter US short 500 lb 500*453.59237/1000 = 226.79618,5 kg
quintal metric 100 kilograms 100 = 100.0 kg
scruple apoth 20 grains 20*453.59237/7000 = 1.29597,82 g
stone Brit 14 lb 14*453.59237/1000 = 6.35029,318 kg
ton long 2240 lb 2240*453.59237/1000 = 1016.04690,88 kg
ton metric mt 10^6 g 1000 = 1000.0 kg
ton US 2000 lb 2000*453.59237/1000 = 907.18474 kg
================================================================================
Units of time (SI second)
One Definition Equivalent to SI units
----------------- --------------- --------------------- = ----------------------
day 24 hours 60*60*24 = 86400.0 s
hour 60 minutes 60*60 = 3600.0 s
mean solar day =~ 86400 sec 86400 =~ 86400.0 s
minute 60 seconds 60 = 60 s
month 28 days 28 days 28*86400 = 24,19200.0 s
month 29 days 29 days 29*86400 = 25,05600.0 s
month 30 days 30 days 30*86400 = 25,92000.0 s
month 31 days 31 days 31*86400 = 26,78400.0 s
month ave 365.2425/12 d 30.43687,5*86400 = 26,29746.0 s
second see second of time: 1 = 1 s
tropical year J1900.0 365.24219,87812,5 days= 315,56925.9747 s
tropical year J2000.0 365.24218,967 days = 315,56925.18748,8 s
week 7 days 7*86400 = 6,04800.0 s
year Julian 365.25 days 365.25*86400 = 315,57600.0 s
year Gregorian 365.2425 days 365.2425*86400 = 315,56952.0 s
year leap 366 days 366*86400 = 316,22400.0 s
year normal 365 days 365*86400 = 315,36000.0 s
Light-time of A tau_A 499.0047863852 = 499.0047863852 s
================================================================================
Units of temperature measurement (SI degrees Kelvin K)
One Definition Equivalent to SI units
----------------- --------------- --------------------- = ----------------------
degrees Celsius C K-273.15 1 = 1 deg K
degrees Fahrenheit F R-459.6 5/9 = 0.555... deg K
degrees Kelvin K 5/9 R 1 = 1 deg K
degrees Rankine R 9/5 K 5/9 = 0.555... deg K
degrees Reaumur Re 4/5 C 5/4 = 1.25 deg K
Absolute zero temp. = -273.15 C = -459.67 F = 0.00 K = 0.0 R = -218.52 Re
Freezing point of water = 0.00 C = 32.00 F = 273.15 K = 491.67 R = 0.00 Re
Boiling point of water = 100.00 C = 212.00 F = 373.15 K = 671.67 R = 80.00 Re
C = (F-32)*5/9 = K-273.15 = (R-491.67)*5/9 = Re*5/4
F = C*9/5 + 32 = K*9/5 - 459.67 = R - 459.67 = Re*9/4 + 32
K = C + 273.15 = (F+459.67)*5/9 = R*5/9 = Re*5/4 + 273.15
R = C*9/5 + 491.67 = F+459.67 = K*9/5 = Re*9/4 + 491.67
Re =C*4/5 = (F-32)*4/9 = (K-273.15)*4/5 = (R-491.67)*4/9
================================================================================
Units of electrical current (SI ampere A)
One Definition Equivalent to SI units
----------------- --------------- --------------------- = ----------------------
abampere abA 10 A 10 = 10 A
ampere A 1 = 1 A
statampere sA 0.3335641e-9 = 0.3335641e-9 A
================================================================================
Units of electrical charge (SI coulomb C)
One Definition Equivalent to SI units
----------------- --------------- --------------------- = ----------------------
abcoulomb abC 10 C 10 = 10 C
coulomb C 1 = 1 C
statcoulomb sC 0.3335641e-9 = 0.3335641e-9 C
1 coulomb = ampere*second = 299792458.0 cm*(dyne)^(1/2)
1 electronic unit charge = 1 e = 0.16021,7653e-18 coulombs
================================================================================
Units of luminous (SI candela cd)
One Definition Equivalent to SI units
----------------- --------------- --------------------- = ----------------------
candela cd 1 = 1.0 cd
================================================================================
Units of amount of substance (SI mole mol)
One Definition Equivalent to SI units
----------------- --------------- --------------------- = ----------------------
Mole mol 1 = 1.0 mol
================================================================================
Units of 2D angular measurement (SI radian)
One Definition Equivalent to SI units
----------------- --------------- --------------------- = ----------------------
circle 2*pi radians 2*pi =~6.28318,53071,79586,48
circumference 2*pi radians 2*pi =~6.28318,53071,79586,48
degree pi/180 radians pi/180 =~0.01745,32925,19943,30
grade pi/200 radians pi/200 =~0.01570,79632,67948,97
minute ang 1 degree / 60 pi/180/60 =~0.00029,08882,08665,72
quadrant pi/2 pi/2 =~1.57079,63267,94896,62
radian 1 = 1.0
revolution 2*pi radians 2*pi =~6.28318,53071,79586,48
right angle 90 degrees pi/2 =~1.57079,63267,94896,62
second ang minute ang/60 pi/180/3600 =~0.00000,48481,36811,10
straight angle 180 degrees pi =~3.14159,26535,89793,24
================================================================================
Units of 3D solid angular measurement (SI steradian)
One Definition Equivalent to SI units
----------------- --------------- --------------------- = ----------------------
space entire 4*pi 4*pi steradians =~12.56637,06143,59173,0
spherical degree 2*Pi/360 pi/180 steradians =~0.01745,32925,19943,30
spherical right angle 4*pi/8 pi/2 steradians =~1.57079,63267,94896,62
sq degree (pi/180)^2 (pi/180)^2 steradians =~0.00030,46174,19786,71
================================================================================
Units of speed (SI meter/sec)
One Definition Equivalent to SI units
----------------- --------------- --------------------- = ----------------------
c speed of light 299792458 = 2997,92458.0 m s-1
mile/min statute mi/min 0.0254*12*5280/60 = 26.8224 m s-1
mile/sec statute mi/sec 0.0254*12*5280 = 1609.344 m s-1
kilometer/hr 1000 m/hr 1000/3600 = 0.2777... m s-1
in/sec inch/second 0.0254 = 0.0254 m s-1
ft/sec foot/second 0.0254*12 = 0.3048 m s-1
mile/hr statute mi/hr 0.0254*12*5280/3600 = 0.44704 m s-1
knot Int 1852 m/hr 1852/3600 = 0.51444... m s-1
meter/sec 1 meter/sec 1 = 1.0 m s-1
centimeter/sec cm/s 1/100 = 0.01 m s-1
================================================================================
Units of acceleration (SI meter/sec^2)
One Definition Equivalent to SI units
----------------- --------------- --------------------- = ----------------------
centimeter/sec^2 1 cm/s^2 1 = 0.01 m s-2
ft/min^2 0.0254*12/60^2 = 0.00008,4666...m s-2
ft/sec^2 foot/second 0.0254*12 = 0.3048 m s-1
gravity g0 g lat=0 h=0 9.780490 = 9.78049,0 m s-2
gravity g90 g lat=90 h=0 9.832213 = 9.83221,3 m s-2
in/sec^2 inch/second 0.0254 = 0.0254 m s-1
meter/min^2 1 meter/min^2 1/60^2 = 0.00027,77... m s-2
meter/sec^2 1 meter/sec^2 1 = 1.0 m s-2
================================================================================
Units of force measurement (SI newton)
One Definition Equivalent to SI units
----------------- --------------- --------------------- = ----------------------
dyne dyn 10^-5 newton 10^-5 = 0.00001 N
Gram-force gf 980.665 dynes 0.00980665 = 0.00980,665 N
kilogram-force 1 kgf =1000 gf 9.80665 = 9.80665 N
newton N 1 kg-m s-2 1 = 1.0 N
ounce-force avdp 0.45359237*9.80665/16 =0.27801,38509,53781,25N
pound-force lbf avdp 0.45359237*9.80665 = 4.44822,16152,605 N
pound-force lbf avdp 9.80665/(0.0254*12) =~32.17404,85564,304 pdl
poundal pdl 1 lb-ft s-2 0.45359237*0.0254*12 = 0.13825,49543,76 N
================================================================================
Units of Gold (1 karat = 1/24 of pure gold)
One Definition Equivalent to SI units
----------------- --------------- --------------------- = ----------------------
karat or carat 1/24 pure gold 1000/24 = 41.666... mg g^-1
================================================================================
Fundamental exact constants and definitions
--------------------------------------------------------------------------------
acre Int: acre International = (5280 ft)^2 / 640 = 43560 sq ft.
acre US survey: (5280 ft USs)^2 / 640 = 43560 sq ft USs.
ampere A: This is the SI unit of electric current, defined as the current which,
if maintained in two straight parallel conductors of infinite length and
negligible circular cross section placed 1 meter apart in vacuum, will produce
between them a force equal to 0.2e-6 newton per meter length. It is named after
the French physicist Andre Marie Ampere (1775-1836).
1 A = (1/0.16021,7653e-18) e/s = 30e3*(10 N)^(1/2) m/s = 1 C/s
Where e = electronic unit of charge, C = coulomb, and N = newton.
So, one ampere of current represents one coulomb of electrical charge
(1/0.16021,7653e-18 charge carriers) moving past a specific point in one second.
Physicists consider current to flow from relatively positive points to
relatively negative points; this is called conventional current or Franklin
current.
astronomical unit A: mean distance Earth to Sun = c*tau_A = 2997,92458.0 *
499.00478,63852 =~ 14,95978,71464.184 m.
barrel US dry: 7056 cu in.
bushel US ah (apples heaped): 2747.715 cu in (apples heaped).
bushel US dry: 2150.42 cu in (stricken bushel).
bushel US heaped: 2688.025 cu in = 1.25 bushel US dry.
candela cd: The candela is the SI unit of luminous intensity. It is the luminous
intensity, in the direction of the normal, of a blackbody surface 1/600000
square meter in area, at a temperature of solidification of platinum (2042 K)
under the pressure of 1 physical atmosphere (1 atmosphere = 101325 pascals).
circular inch: area of circle with diameter 1 inch.
circular mil: area of circle with diameter 10^-3 inches.
circular mm: area of circle with diameter 1 mm.
coulomb C: This is the SI unit of quantity of electricity, defined as the
quantity of electric charge transported in 1 second by a current of 1 ampere. It
is named after Charles-Augustin de Coulomb (1736-1806).
1 C = (1/0.16021,7653e-18) e = 30e3*(10 N)^(1/2) m = 1 ampere*second = 1 A-s
Where e = electronic unit of charge, C = coulomb, and N = newton.
dalton: Da = unified atomic mass unit u = 1/12 the mass of an atom of carbon-12
=~1.660538728e-24 g. Named after John Delton. Da = 1/NA gram (where NA is
Avogadro's number = 6.02214,199e23 +/- 0.00000,047e23. Amadeo Avogadro (1776-
1856). Avogadro's number is the number of atoms present in 12 grams of the
carbon-12 isotope (one mole of carbon 12)).
degree of angle: defined by there being 360 degrees in a circle.
drachm: traditional British spelling of dram
gallon Imp liq: 4.54609 L.
gallon US liq: 231 cu in. = old English wine gallon
grain: The common element in troy, apothecaries', and avoirdupois weight: the
troy and apothecaries' pound are 5,760 grains, and the pound avoirdupois is
7,000 grains.
gravity: earth gravitational acceleration, the variation of earth-surface
gravitational acceleration g(lat) with geocentric latitude is given by the
International Gravity Formula adopted in 1930 by the International Geophysical
Congress.
g(lat) = 978.049*(1 + 0.00528,84*sin^2(lat) - 0.00000,59*sin^2(2*lat)
where g is in cm s-2 and lat in degrees. g0 = g(0) = 9.78049,0 m s-2
g90 = g(90) = 9.83221,3 m s-2
inch (US survey): = 1000/39.37 mm.
inch: in = 25.4 mm. Effective July 1, 1959 the British and US yard was defined
to be the same and equal to 0.9144 m.
karat gold: 24-karat gold is pure gold (karat or carat)
Kelvin K: The Kelvin is the SI unit of temperature. It is 1/273.16th of the
thermodynamic temperature of the triple point of water. It is named after the
Scottish mathematician and physicist William Thomson 1st Lord Kelvin (1824-
1907).
kilogram kg: mass of international prototype of kg.
light time of A (astronomical unit) tau_A: 499.00478,63852 s (SI).
light year ly: distance light travels in a standard tropical year of
315,56925.9747 s = 315,56925.9747*2997,92458 = 9,46052,84048,79358.8126 m.
liter L: 1000 cu cm.
meter: since 1983, the meter is the length of the path traveled by light in
vacuum during a time interval of 1/299,792,458 of a second. Note that the effect
of this definition is to fix the speed of light in vacuum at exactly 299,792,458
m s-1.
mole mol: The mole is the SI unit of substance. It is the amount of substance
that contains the same number of elementary particles as there are atoms in 12
grams of pure nuclide carbon-12.
parsec: The parsec is defined to be the distance from the Earth of a star that
has a parallax of 1 arc second. Alternatively, the parsec is the distance at
which two objects, separated by 1 astronomical unit, appear to be separated by
an angle of one arc second. It is, therefore, approximately: A*360*60*60/(2*pi)
= 2997,92458.0 * 499.00478,63852 * 360*60*60/(2*pi) =~
3.08567,75972,53794,63188�10^16 m =~ 30.85677... Pm (pentameters).
pi: a transcendental number, approximately 3.14159, represented by the 16th
letter of the Greek alphabet pi that expresses the ratio of the circumference to
the diameter of a circle.
point: computer point or PostScript point defined as 1/72 of an inch or
0.352777... mm by Warnock and Geschke, the inventors of Adobe PostScript. Now
the universal point in computer typesetting.
pound avdp: lb = 453.59237 g.
radian: defined by there being 2*pi radians in a circle.
second of time: since 1967, the second is the duration of 9,192,631,770 periods
of the radiation corresponding to the transition between the two hyperfine
levels of the fundamental (ground) state (at a temperature of 0 K) of the atom
cesium 133.
Size: American pocket watch sizes, remember, this is a measure of the diameter
of the movement, not the case. Sizes range from 6/0 (6 ought), 5/0, ..., 2/0, 0,
1, 2, 3, ..., 20. A size 6/0 is exactly 1 inch in diameter and each size is
exactly 1/30 inch larger than the previous size. This makes a size 1 watch 36/30
inches.
speed of light: c = 299,792,458 m s-1.
steradian: defined by there being 4*pi steradians in entire 3 dimensional space.
township: 6 miles on southern border, a parallel, 6 miles on eastern and
western borders, a latitude lines, and less than 6 miles on the northern border,
a parallel. Therefore, a township can be smaller than 6 miles by 6 miles due to
northern border being less than 6 miles (assumes a northern country like USA).
tropical year: 365.24219,87812,5 - 6.14 x 10-6 TE) days where TE is Julian
centuries from day 0.5, 1900 Ephemeris Time
tropical year, mean: (averaged over all ecliptic points) is: 365.24218,967 days
(365 d 5 h 48 min 45.18748,8 s) = 315,56925.18748,8 (at the epoch J2000.0).
tropical year, standard: at day 0.5, 1900 ephemeris time = 315,56925.9747 s =
315,56925.9747/86400 = = 365.24219,87812,5 days.
Abbreviations of units:
Y = yotta = 10^24
Z = zetta = 10^21
E = exa = 10^18
P = peta = 10^15
T = tera = 10^12
G = giga = 10^9
M = mega = 10^6
k = kilo = 10^3
h = hecto = 10^2
da = deka or deca = 10^1
d = deci = 10^-1
c = centi = 10^-2
m = milli = 10^-3
u = micro = 10^-6
n = nano = 10^-9
p = pico = 10^-12
f = femto = 10^-15
a = atto = 10^-18
z = zepto = 10^-21
y = yocto = 10^-24
Abbreviations:
... = and so forth, 0.333... = 1/3 exactly
=~ = approximately equal
2D = 2 dimensional
3D = 3 dimensional+-
A = astronomical unit
ah = apples heaped
ang = angular
apoth = apothecary system of weights, grain, scruple, drachma, ounce
avdp = avoirdupois system of weights, dram, ounce, pound
ave = average
Bd = British dry measure
Bl = British liquid measure
Brit = Imp = British Imperial system of weights = avoirdupois
cc = cu cm = cm^3
cu = cubic
Da = dalton
dwt = pennyweight
e = exponent, like 1.0e9 = 1.0*10^9
ft = foot
g = gram
G = Gunter's (US & UK) = Edmund Gunter = Gunther's = surveyor's chain
gal = gallon
hr = hour
hundredwgt = hundredweight
in = inch
Int = international
L = liter
lb = pound avoirdupois
liq = liquid = fluid
ly = light year
m = meters
min = minute of time
mL = milliliter
naut = nautical
old Eng = old English measure prior to the 1824 imperial measure.
petro = petroleum
R = Ramden's (US) = Ramsden's = engineer's chain
s = sec = second of time
size watch US 1 = a size 1 US watch
size watch US d = delta US watch size
sq = square
troy = troy system of weights, grain, pennyweight, ounce, pound
UK = United Kingdom
US = United States of America
USl = US liquid measure
USN = US Navy
USs = survey = United States survey
vol = volume
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times since October 29, 2005.