mathematical relation between numerical quantity values, based on a given quantity equation and specified measurement units
EXAMPLE 1 For the quantities in Example 1 in item 1.22, {Q1} = ζ{Q2} {Q3} where {Q1}, {Q2}, and {Q3} denote the numerical values of Q1, Q2, and Q3, respectively, provided that they are expressed in either base units or coherent derived units or both.
EXAMPLE 2 In the quantity equation for kinetic energy of a particle, T = (1/2) mv2, if m = 2 kg and v = 3 m/s, then {T} = (1/2) ·2 ·32 is a numerical value equation giving the numerical value 9 of T in joules.
ANNOTATION (informative) [1 December 2014] Here "numerical quantity value" can be replaced with "numerical value" in the definition without ambiguity: "mathematical relation between numerical values, based on a given quantity equation and specified measurement units".