Appendix 2

Unit Conversion Tables

An inordinate amount of time can be spent in looking up tables of conversion factors. Therefore, as a gesture of convenience, the following Conversion Tables for units used in this book, are included for those readers who may wish to convert existing Imperial or Metric units to SI units and vice versa. Where a factor is followed by the exponent E, a plus (+) or minus (−) sign and two digits indicate the power of 10 by which the factor is multiplied.

For example:

E–02 means 10−2 and 30.48 E–02 = 30.48 × 10−2 = 0.3048

E+04 means 104 and 2.832 E+04 = 2.832 × 104 = 28 320

SI Base Units and Quantities

In the SI system (Système Internationale d'Unités) there are seven base units for seven base quantities that are assumed to be mutually independent. The seven base units and quantities are shown in Table A.2.1.

Table A.2.1 SI Base Units.

Base quantity SI base unit
Name Symbol
Length metre m
Mass kilogram kg
Time second s
Electric current ampere A
Thermodynamic temperature Kelvin K
Amount of substance mole mol
Luminous intensity candela cd

SI Derived Units and Quantities

SI derived quantities are defined in terms of the seven base quantities given in Table A.2.1 via a system of quantity equations. The SI derived units for these derived quantities are obtained from these equations and the seven base units given in Table A.2.1. Some examples of SI derived quantities and units are given in Table A.2.2.

Table A.2.2 Some Examples of ...

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