In the equation ${ }_{13}^{27} Al + { }_2^4 He \longrightarrow { }_{15}^{30} P + X$,the correct symbol for $X$ is:

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 $10^{-4} \; m$.

On the bombardment of a neutron with Boron,an $\alpha$-particle is emitted. The product nucleus formed is:

Which statement is true for the nuclear force?

In the nuclear reaction $_2He^4 + _zX^A \to _{z+2}Y^{A+3} + A$,$A$ denotes:

The electric potential at the surface of an atomic nucleus $(Z=50)$ of radius $9 \times 10^{-15} \,m$ is