Physical Chemistry of Foods

Appendix E

The SI Units System

SI stands for ‘‘Syste`me International,’’ and the SI System of Units concerns
the internationally accepted and standardized rules for the values and the
notation of units for physical quantities. One basic rule is that

Quantity¼number 6 unit

Furthermore, it is ametricsystem, all units for the same quantity differing
by one or more factors of 10.

Base Units

These concerns the units for some measurable, dimensionally independent
quantities from which all other units can be derived. The magnitude of each
base unit has been unequivocally and precisely defined.

Quantity Name Symbol

Length meter m
Mass kilogram kg
Time second s
Electric current ampere A