If $r_1$ and $r_2$ are the radii of the atomic nuclei of mass number $64$ and $125$ respectively,then the ratio $(r_1/r_2)$ is

Which of the following pairs of nuclei are isobars?

Which of the following figures represents the variation of $\ln \left(\frac{R}{R_{0}}\right)$ with $\ln A$ (where $R =$ radius of a nucleus and $A =$ its mass number)?

$A$ nucleus ruptures into two nuclear parts which have their velocity ratio equal to $2 : 1$. What will be the ratio of their nuclear size (nuclear radius)?

If the nuclear radius of ${}_{13}^{27}Al$ is $3.6 \, fm$,the approximate nuclear radius of ${}_{29}^{64}Cu$ in fermi is .......... $fm$.

$A$ nucleus has mass number $A_1$ and volume $V_1$. Another nucleus has mass number $A_2$ and volume $V_2$. If the relation between mass numbers is $A_2 = 4 A_1$,then $\frac{V_2}{V_1} = $ . . . . . . .