Radioactivity is

Give a brief explanation about radioactivity.

The number of beta particles emitted by a radioactive substance is twice the number of alpha particles emitted by it. The resulting daughter nucleus is an

Which ray contains positively charged particles?

Obtain the maximum kinetic energy of $\beta$-particles and the radiation frequencies of $\gamma$-decays in the decay scheme shown in the figure. You are given that:
$m(^{198}Au) = 197.968233 \; u$
$m(^{198}Hg) = 197.966760 \; u$

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 . . . . . . .