Select the correct relation from below if u₁ and u₂ are the units selected in two systems of measurement and n₁ and n₂ are their numerical values.

Since u is assumed as unit system and n as numerical value

Hence, a physical quantity is given by Physical quantity (p) = (n)  (u)
For a given physical quantity, the product of number and unit is same for different system of units.

${\mathrm{n}}_1^{ }{\mathrm{u}}_1={\mathrm{n}}_2^{ }{\mathrm{u}}_2$