ABSTRACT
The physical quantities commonly dealt with in scientific investigations and production processes are usually quantified. They are measured in some or the other unit. Further, the quantity is expressed as a numerical value, which characterises the quantity irrespective of whether it has been measured by experimental methods or mathematical expressions. Length can similarly be made non-dimensional by measuring it as a ratio to a fixed unit length. However, it is convenient to measure an angle by a fixed unit since its value does not change with change in scale of the object. An increase in number of fundamental quantities is associated with the introduction of new dimensional physical constants, whereas a decrease in number of fundamental quantities makes physical constants absolute and they become absolute non-dimensional quantities. A unique phenomenon is a member of a class of physical phenomena which differs from the others by numerical values of some given quantities or parameters.
