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. (march 2017)
in dimensional analysis, a dimensionless quantity is a quantity to which no physical dimension is assigned, also known as a bare, pure, or scalar quantity or a quantity of dimension one, with a corresponding unit of measurement in the si of the unit one (or 1), which is not explicitly shown. dimensionless quantities are widely used in many fields, such as mathematics, physics, chemistry, engineering, and economics. an example of a quantity that has a dimension is time, measured in seconds.