Units of Measurement
The value of a physical quantity is given according to a standard called “Unit”, the units of physical quantities are written according to that of fundamental quantities.
The International System of Units (SI system)
The international system of units SI [1]or MKSA system consists of 7 base units adapted to 7 physical quantities, as shown in the following table[2]
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Note :
Dimensions aren't the same as units; dimension of physical quantities is its physical nature. For example, the physical quantity, speed, may be measured in units of meters per second, miles per hour etc.; but regardless of the units used, speed is always a length divided a time, so we say that the dimensions of speed are length divided by time.