Practical Norms for the use of SI system

1. Unit of every physical quantity should be represented according to its symbol.


2. No full stop should be used within or at the end of the symbol for a unit. For example, for kilogram, kg should be written instead of kg. or k.g.


3. Symbols for unit do not take plural form. For example m is used to denote many meters also.


4. The units of physical quantities in numerator and denominator should be written as one ratio only. For example the SI unit of acceleration should be written either as m/s²
   or m s^-2; but not as m/s/s.


5. Full name of a unit, when it is named after a scientist, is not written with a capital letter; but the symbol for that unit has a capital letter. For example, the unit of force should be written as newton but in symbol it is written as N. The symbol for the unit of pressure (viz. pascal) is written in symbol as Pa.