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SI system

Only length, mass and time are measured in the above mentioned
system of units. But we have to measure several other physical
quantities in our daily life . Hence, the international conference of the
scientists in 1960 AD decided to adopt a new system of measurement
which can measure all physical quantities. This system is called SI
system and the units used in this system are called SI units.

The system of the units that was adopted by the international
convention of scientist in 1960 AD in France is called SI system. The
units of measurement which are used in SI system are called SI units.

The full form of SI units is ‘system international de units’. The SI
system is the extended and improved form of MKS system and is
used all over the world.

The SI units are divided into two groups. They are fundamental units
and derived units.

Fundamental units

The units which do not depend on other units are called fundamental
units. The fundamental units are also known as basic units. The unit
of mass, length, time, temperature, etc are fundamental units. The
fundamental units are given in the following table :

S.N. Fundamental quantities Fundamental units Symbol

1 Length Metre m

2 Mass Kilogram kg

3 Time Second s

4 Temperature Kelvin K

5 Electric Current Ampere A

6 Amount of Substance Mole mol

7 Luminous Intensity Candela cd

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