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1. Science Constants
Quick search. Type in a keyword then click Search button.
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.
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Universal
Electromagnetic
Atomic and nuclear
Physico-chemical
Mathematics
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2. Unit Conversions
Quick unit search. Type in a keyword, select unit name, symbol or application (category) type then click Search button.
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).
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Physical Dimensions
Heaviness
Electromagnetic
Chemical & physical
Irradiation
Duration
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3. Survey and Statistics
This section contains poll results on views and opinions of some of the visitors to this web site. The poll questions are largely orientated
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
time, so do remember to cast your vote!
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.
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Space Science
Environment
Global & Society
Education
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Note:
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.
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