Physical Structure

C#
public struct Physical

Visual Basic (Declaration)
Public Structure Physical

Visual C++
public value class Physical

The case of the String specifying the name of the physical constant does not matter. The names 'PI', 'Pi', 'pI' and 'pi' are equivalent.

The units of the physical constants are in SI units, (meter-kilogram-second).

The names allowed are as follows:

Name	Description	Value	Reference
AMU	Atomic mass unit	1.6605402E-27 kg	[1]
ATM	Standard atm pressure	1.01325E+5 $\rm {N / m^2}$	E[2]
AU	Astronomical unit	1.496E+11 m	[ ]
Avogadro	Avogadro's number	6.0221367E+23 1/mole	[1]
Boltzman	Boltzman's constant	1.380658E-23 J/K	[1]
C	Speed of light	2.997924580E+8 m/s	E[1]
Catalan	Catalan's constant	0.915965...	E[3]
E	Base of natural logs	2.718...	E[3]
ElectronCharge	Electron change	1.60217733E-19 C	[1]
ElectronMass	Electron mass	9.1093897E-31 kg	[1]
ElectronVolt	Electron volt	1.60217733E-19 J	[1]
Euler	Euler's constant gamma	0.577...	E[3]
Faraday	Faraday constant	9.6485309E+4 C/mole	[1]
FineStructure	Fine structure	7.29735308E-3	[1]
Gamma	Euler's constant	0.577...	E[3]
Gas	Gas constant	8.314510 J/mole/K	[1]
Gravity	Gravitational constant	6.67259E-11 $\rm {Nm^2/{\rm {kg}}^2}$	[1]
Hbar	Planck constant / 2 pi	1.05457266E-34 J*s	[1]
PerfectGasVolume	Std vol ideal gas	2.241383E-2 $\rm {m^3/ {\rm {mole}}}$	[*]
Pi	Pi	3.141...	E[3]
Planck	Planck's constant h	6.6260755E-34 J*s	[1]
ProtonMass	Proton mass	1.6726231E-27 kg	[1]
Rydberg	Rydberg's constant	1.0973731534E+7 /m	[1]
SpeedLight	Speed of light	2.997924580E+8 m/s	E[1]
StandardGravity	Standard g	9.80665 $\rm {m/s^2}$	E[2]
StandardPressure	Standard atm pressure	1.01325E+5 $\rm {N/m^2}$	E[2]
StefanBoltzmann	Stefan-Boltzman	5.67051E-8 $\rm {W/K^4/m^2}$	[1]
WaterTriple	Triple point of water	2.7316E+2 K	E[2]

The reference for constants are indicated by the code in the [] comment above.

[1]	Cohen and Taylor (1986)
[2]	Liepman (1964)
[3]	Precomputed mathematical constants

The constants marked with an E before the [] are exact (to machine precision).

Units strings have the form U1*U2*...*Um/V1/.../Vn, where Ui and Vi are the names of basic units or are the names of basic units raised to a power. Examples are, 'METER*KILOGRAM/SECOND', 'M*KG/S', 'METER', or ' $\rm {M/KG^2}$ '. These strings are case insensitive.

The basic unit names allowed are as follows.

Units of time

day, hour = hr, min = minute, s = sec = second, year

Units of frequency

Hertz = Hz

Units of mass

AMU, g = gram, lb = pound, ounce = oz, slug

Units of distance

Angstrom, AU, ft = feet = foot, in = inch, m = meter = metre, micron, mile, mill, parsec, yard

Units of area

acre

Units of volume

l = liter = litre

Units of force

dyne, N = Newton, poundal

Units of energy

BTU(thermochemical), Erg, J = Joule

Units of work

W = watt

Units of pressure

ATM = atomosphere, bar, Pascal

Units of temperature

degC = Celsius, degF = Fahrenheit, degK = Kelvin

Units of viscosity

poise, stoke

Units of charge

Abcoulomb, C = Coulomb, statcoulomb

Units of current

A = ampere, abampere, statampere

Units of voltage

Abvolt, V = volt

Units of magnetic induction

T = Tesla, Wb = Weber

Other units

1, farad, mole, Gauss, Henry, Maxwell, Ohm

The following metric prefixes may be used with the above units. Note that the one or two letter prefixes may only be used with one letter unit abbreviations.

A = atto = 1.E-18

F = femto = 1.E-15

P = pico = 1.E-12

N = nano = 1.E-9

U = micro = 1.E-6

M = milli = 1.E-3

C = centi = 1.E-2

D = deci = 1.E-1

DK = deca = 1.E+1

K = kilo = 1.E+3

myria = 1.E+4 (no single letter prefix; M means milli)

mega = 1.E+6 (no single letter prefix; M means milli)