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quanta.constants - Function

1.5.1 get a constant


Description

constants gets a named constant quantity. Names (no-case, minimax) are:

pi 3.14.. 3.14159 ee 2.71.. 2.71828 c light vel. 2.99792e+08 m/s G grav. const 6.67259e-11 N.m2/kg2 h Planck const 6.62608e-34 J.s HI HI line 1420.41 MHz R gas const 8.31451 J/K/mol NA Avogadro number 6.02214e+23 mol-1 e electron charge 1.60218e-19 C mp proton mass 1.67262e-27 kg mp_me mp/me 1836.15 mu0 permeability vac. 1.25664e-06 H/m eps0 permittivity vac. 1.60218e-19 C k Boltzmann const 1.38066e-23 J/K F Faraday const 96485.3 C/mol me electron mass 9.10939e-31 kg re electron radius 2.8179e-15 m a0 Bohr’s radius 5.2918e-11 m R0 solar radius 6.9599e+08 m k2 IAU grav. constˆ2
0.000295912 AU3/d2/S0

Arguments





Inputs

v

name

allowed:

string

Default:

pi

Returns
record

Example

 
 
"""  
#  
print "\t----\t constants Ex 1 \t----"  
print qa.constants()  
#{’unit’: ’’, ’value’: 3.1415926535897931}  
#  
"""  
 

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