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

The electric potential at the surface of an atomic nucleus $(Z = 50)$ of radius $9.0 \times 10^{-15} \, m$ is

Are the nucleons fundamental particles,or do they consist of still smaller parts? One way to find out is to probe a nucleon just as Rutherford probed an atom. What should be the kinetic energy of an electron for it to be able to probe a nucleon? Assume the diameter of a nucleon to be approximately $10^{-15} \ m$.

Out of gravitational,electromagnetic,Van der Waals,electrostatic,and nuclear forces,which two are able to provide an attractive force between two neutrons?

The nuclear forces are

The graph of $\ln \left(\frac{R}{R_0}\right)$ versus $\ln A$ is,where $R$ is the radius of a nucleus,$A$ is its mass number,and $R_0$ is a constant.