Units of Measurement

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Units
What are the Units?

The laws of physics require  measurement and comparison of physical quantities for their description.

▪Just like, If we need to know that whether “Alex” is heavy or  “Clay”.
▪In that case, we will have to measure the mass of Alex and Clay.
▪But for the measurement of their masses, we need units such as kg, pound, etc.
▪Thus, the physical quantities are quantitatively expressed in terms of a unit of that quantity.

Who decides the Units?

▪A body named General Conference on Weight and measures (also known as CGPM) has been given the authority to decide the units by international agreement.
▪In 1971, CGPM held it’s meeting and decided a system of units which is known as the International System of units.
▪This system is known as S.I. system and this is widely used throughout the world.

What are the types of units?
Types of the units are basically, Fundamental Units and Derived Units depending on Quantity.

Basically, There are two types of Quantities.

1.Fundamental Quantities: They don’t need any other units for their measurements. Ex. Mass, Length, Time, Current, etc.
2.Derived Quantities: They are dependent on fundamental units for their measurements. Ex. Force, Energy, Work done, etc.
Fundamental Units:
There are 7 Fundamental Quantities,
And 2 Supplementary Units,
Derived Quantities:
Some Derived Quantities are given below,
The End













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