Assertion : When we change the unit of measurement of a quantity, its numerical value changes.\ Rea

Question

Assertion : When we change the unit of measurement of a quantity, its numerical value changes.\ Reason : Smaller the unit of measurement smaller is its numerical value.

Professor PC Thomas Classes · Answer

(c) : If $u_1$ and $u_2$ are the units to measure a quantity $Q$ and $n_1$ and $n_2$ are the numerical values respectively then we know that $Q=n_1 u_1=n_2 u_2$. Since the quantity $Q$ does not change irrespective of the units used to measure it $Q=$ constant. So $n u=$ constant $\Rightarrow n \propto \frac{1}{u}$ i.e. smaller the unit of measurement, greater is the corresponding numerical value.