If the size of a nucleus (in the range of $10^{-15} \; m$ to $10^{-14} \; m$) is scaled up to the tip of a sharp pin,what roughly is the size of an atom (in $; m$)? Assume the tip of the pin to be in the range $10^{-5} \; m$ to $10^{-4} \; m$.

The charge density $P$ in a nucleus varies with distance $r$ from the centre of the nucleus according to the curve in the figure. Which of the following graphs correctly represents this variation?

The distance between two nucleons for which the potential energy is minimum,is (in $fm$)

Given below are two statements: one is labelled as Assertion $A$ and the other is labelled as Reason $R$.
Assertion $A$: The nuclear density of nuclides ${ }_{5}^{10} B, { }_{3}^{6} Li, { }_{26}^{56} Fe, { }_{10}^{20} Ne$ and ${ }_{83}^{209} Bi$ can be arranged as $\rho_{ Bi }^{ N } > \rho_{ Fe }^{ N } > \rho_{ Ne }^{ N } > \rho_{ B }^{ N } > \rho_{ Li }^{ N }$.
Reason $R$: The radius $R$ of a nucleus is related to its mass number $A$ as $R = R_0 A^{1/3}$,where $R_0$ is a constant.
In the light of the above statements,choose the correct answer from the options given below:

Which of the following pairs of nuclei represents isotones?

For a nucleus of mass number $A$ and radius $R$,the mass density of the nucleus can be represented as: