1. Science Constants
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All constants are categorized into five different groups as shown on the right. The constants are listed in alphabetical order in each group.
Universal - Fundamental invariant quantities that usually appear in basic theoretical equations in all aspects of science.
Electromagnetic - General electronic and magnetic behavior.
Atomic and nuclear - Values relate to atomistic world, including sub-particles.
Physico-chemical - Quantities usually encounter in chemical physics.
Mathematics - Mathematical constants
with no units, usually can be derived from mathematical equations.
Atomic and nuclear
2. Unit Conversions
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All measurement units are categorized into six different groups as shown on the right. The quantities are listed in alphabetical order in each group, with some
examples of unit application (category) type are also given.
Physical dimension - Length, area, volume.
Heaviness - Mass, weight etc.
Electromagnetic - Electronic, magnetic
Chemical & physical - Energy, power, force, heat, thermodynamic etc.
Irradiation - emission of light, radioactivity etc.
Duration - Time, year, era etc.
Click here to find out more about the SI units (see Note below).
Chemical & physical
3. Survey and Statistics
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towards popular topics in science and technology. I would like to give my thanks to those who have participated in the poll! New poll questions will be posted from time to
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Space Science - Space exploration, policy and astronomy.
Environment - Renewable energy, policy, problems.
Global & Society - Issues concerning the whole world and to the society.
Education - Issues regarding science in education.
Global & Society
The science constant values obtained from 1998 Committee on Data for Science and Technology (CODATA) recommeded values. Derivation of values can be found in (1) Journal of Physical and Chemical Reference Data, vol. 28, No. 6, p1713-1852 (1999) and
(2) Reviews of Modern Physics, vol. 72, No. 2, p351-495 (2000).
The last 2 digits in brackets are the uncertainty of values. Values list are exact if they do not have this uncertainty.
The International System of Units (Le Systeme International d'Unités) or the SI units are the standardized, internationally accepted units. All other informal or colloquial units listed are shown in the SI unit equivalent. Up to date (2002), there are 7
fundamental or base SI units and 2 supplementary SI units of which all known units can be derived.