The atoms of the same element having different masses but same chemical properties are called:

Calculate the height of the potential barrier for a head-on collision of two deuterons. (Radius of deuteron is $2$ fm).

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.

The ratio of the nuclear radii of the gold isotope ${}_{79}^{197}Au$ and the silver isotope ${}_{47}^{107}Ag$ is $ . . . . . . $.

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

The radius $R$ of a nucleus of mass number $A$ can be estimated by the formula $R = (1.3 \times 10^{-15}) A^{1/3} \; m$. It follows that the mass density of a nucleus is of the order of $(M_{\text{prot}} \cong M_{\text{neut}} = 1.67 \times 10^{-27} \; kg)$.