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".