$A$ nucleus of mass $218\, amu$ in a free state decays to emit an $\alpha$-particle. The kinetic energy of the emitted $\alpha$-particle is $6.7\, MeV$. The recoil energy (in $MeV$) of the daughter nucleus is:

Pauli suggested the emission of neutrino during $\beta^{+}$ decay to explain:

Radioactivity is a/an ...... process.

Two radioactive substances $A$ and $B$ of mass numbers $200$ and $212$ respectively, show spontaneous $\alpha$-decay with the same $Q$ value of $1 \text{ MeV}$. The ratio of energies of $\alpha$-rays produced by $A$ and $B$ is . . . . . . .

The energy spectrum of $\beta$-particles [number $N(E)$ as a function of $\beta$-energy $E$] emitted from a radioactive source is:

$A$ certain radioactive nuclide of mass number $m_x$ disintegrates,with the emission of an electron and $\gamma$ radiation only,to give a second nuclide of mass number $m_y$. Which one of the following equations correctly relates $m_x$ and $m_y$?