APPENDIX D. UNITS

SI (Systeme Internationale) Units

Physical QuantityName of UnitSymbol
lengthmeterm
masskilogramkg
MultiplePrefixSymbol
103kilok
106megaM
109gigaG
1012teraT
1015petaP
1018exaE

Special Names and Symbols for Certain SI-Derived Units

Physical QuantityName of SI UnitSymbol for SI UnitDefinition of Unit
energyjouleJkg m2 s- 2
powerwattWkg m2 s- 3 (= Js-1)

Decimal Fractions and Multiples of SI Units Having Special Names

Physical QuantityName of UnitSymbol for UnitDefinition of Unit
areahectareha104 m2
weighttont103 kg

Non-SI Units

°Cdegrees Celsius (0°C = ~273K); Temperature differences are also given in°C rather than the more correct form of "Celsius degrees"
kWhkilowatt-hour
MWemegawatts of electricity
ppmvparts per million (106) by volume
ppbvparts per billion (109) by volume
pptvparts per trillion (1012) by volume
tcetons of coal equivalent
toetons of oil equivalent
TWhterawatt-hour


Go to Appendix C. Acronyms and Abbreviations
Go to Appendix E: Glossary of Terms
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