$M_p$ denotes the mass of a proton and $M_n$ that of a neutron. $A$ given nucleus,of binding energy $B$,contains $Z$ protons and $N$ neutrons. The mass $M(N, Z)$ of the nucleus is given by ($c$ is the velocity of light):

Assuming the experimental mass of $^{12}_{6}C$ as $12 \text{ u}$, the mass defect of $^{12}_{6}C$ atom is . . . . . . $\text{u}$. (Mass of proton $= 1.00727 \text{ u}$, mass of neutron $= 1.00866 \text{ u}$).

If the binding energy per nucleon in $_3^7Li$ and $_2^4He$ nuclei are $5.60 \, MeV$ and $7.06 \, MeV$ respectively,then in the reaction $p + {}_3^7Li \to 2 {}_2^4He$,the energy of the proton must be ........... $MeV$.

The neutron separation energy is defined as the energy required to remove a neutron from the nucleus. Obtain the neutron separation energies of the nuclei $_{20}^{41} Ca$ and $_{13}^{27} Al$ from the following data:
$m(_{20}^{40} Ca) = 39.962591 \; u$
$m(_{20}^{41} Ca) = 40.962278 \; u$
$m(_{13}^{26} Al) = 25.986895 \; u$
$m(_{13}^{27} Al) = 26.981541 \; u$
(Given mass of neutron $m_n = 1.008665 \; u$)

The deuteron is bound by nuclear forces just as the $H$-atom is made up of a proton and an electron bound by electrostatic forces. If we consider the force between the neutron and proton in a deuteron as given in the form of a Coulomb potential but with an effective charge $e'$: $F = \frac{1}{4\pi \epsilon_0} \frac{e'^2}{r^2}$,estimate the value of $(e'/e)$ given that the binding energy of a deuteron is $2.2 \text{ MeV}$.

The mass equivalent of $931\, MeV$ energy is