$A$ free nucleus of mass $24 \, amu$ emits a gamma photon (when initially at rest). The energy of the photon is $7 \, MeV$. The recoil energy of the nucleus in $keV$ is:

Write the equation of mass-energy equivalence.

Which of the following statement$(s)$ is/are true in respect of nuclear binding energy?
$(i)$ The mass energy of a nucleus is larger than the total mass energy of its individual protons and neutrons.
(ii) If a nucleus could be separated into its nucleons,an energy equal to the binding energy would have to be transferred to the particles during the separating process.
(iii) The binding energy is a measure of how well the nucleons in a nucleus are held together.
(iv) The nuclear fission is somehow related to acquiring higher binding energy.

What is the order of binding energy per nucleon?

If the total binding energies of ${ }_1^2 H ,{ }_2^4 He ,{ }_{26}^{56} Fe$ and ${ }_{92}^{235} U$ nuclei are $2.22, 28.3, 492$ and $1786 \text{ MeV}$ respectively,identify the most stable nucleus of the following.

$M_n$ and $M_p$ represent the mass of a neutron and a proton, respectively. If an element having atomic mass $M$ has $N$ neutrons and $Z$ protons, then the correct relation is: