OBSOLETE PHYSICAL CONSTANTS 程序包 教程
As of Version 9.0, physical constant functionality is built into the Wolfram Language

# Physical Constants Package

In addition to providing a comprehensive environment for calculations and a programming language, the Wolfram Language is also a system for representing and presenting scientific and technical knowledge. Certain packages are included with the Wolfram Language to provide easy access to commonly used scientific data, such as the value of physical constants and conversion factors for various systems of units.

 SpeedOfLight the speed of light is 299792458 Meter/Second AvogadroConstant Avogadro's constant is approximately 6.02214199×1023Mole^-1 ElectronMass the mass of an electron is approximately 9.10938188×10-31 Kilogram FineStructureConstant the fine structure constant is approximately 7.297352533×10-3 EarthMass the mass of the earth is approximately 5.9742×1024 Kilogram AccelerationDueToGravity the acceleration due to gravity is 9.80665 Meter/Second2

Some common physical constants.

 In[1]:=
This gives the mass of a proton.
 In[2]:=
 Out[2]=
Here is the distance that light could travel in the age of the universe.
 In[3]:=
 Out[3]=

Physical constants.