Sol. Nuclear density is independent of mass numb $$ \text { As nuclear density }=\frac{\mathrm{Au}}{\frac{4}{3} \pi \mathrm{R}^3} $$ Also, $\mathrm{R}=\mathrm{R}_0 \mathrm{~A}^{1 / 3}$ And $R^3=R_0^3 A$ $$ \begin{aligned} & \Rightarrow \text { Nuclear density }=\frac{\mathrm{Au}}{\frac{4}{3} \pi \mathrm{R}_0^3 \mathrm{~A}} \\ & \text { Nuclear density }=\frac{3 \mathrm{u}}{4 \pi \mathrm{R}_0^3} \end{aligned} $$ ⇒ Nuclear density is independent of $A$