MEASUREMENT : Physical Quantities

Physic is experimental study. Most experiments in physics need quantitative observation rather than qualitative observation.Quantitative observation needs some test and mesurement.

A physical quantity is quantity that can be measured and consist of numerical magnitude and a unit.

In order to test and measure physical quantities we need to define some standard measures which we everyone can agree on.  The internationally recognised authority for the definition of these standards is the Conference Generale des Poids et Measures (CGPM). 

The units by which we now measure physical quantities is called the S.I. (System International) system established in 1960. Within this system, the most commonly used set of units in physics are M.K.S (Metres, Kilograms, Seconds) system

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