SI Units

SI Units

Use of different systems of units became inconvenient for exchanging scientific information between different part of the world. Hence Oct. 1960, at the Eleventh International General Conference of weights and measures held in Paris. It decides to have a common system of units called System International d' units.

The international system of units is abbreviated as SI system. The French name for this system is 'system

Internationale d unities'. This system is an improved and extended version of the MKS system of units. The three fundamental units of mass, length and time are sufficient to obtain the units of physical quantities in mechanics quantities which come across in other branches of only, but not sufficient to obtain the units of physical physics like optics, electrodynamics, heat etc.

Therefore, the general conference of weights and measures decided new system of units with the standard scheme of symbols, units and abbreviations called as SI system.

Advantages of the SI system over other systems of units

i) This system makes use of only one unit for one physical quantity.
ii) In this system, all the derived units can be easily obtained from fundamental and supplementary units.
iii) It is a metric system i.e. multiples and submultiples can be expressed as powers of 10, hence conversions within the system are quite simple and convenient.
iv) It is the improved version of two metric systems C.G.S. system and M.K.S. system. In the present study, we use SI units.

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