Alpha rays emitted from a radioactive substance are:

Find the $Q$-value and the kinetic energy of the emitted $\alpha$-particle in the $\alpha$-decay of $(a) \; ^{226}_{88} Ra$ and $(b) \; ^{220}_{86} Rn$.
Given:
$m(^{226}_{88} Ra) = 226.02540 \; u$
$m(^{222}_{86} Rn) = 222.01750 \; u$
$m(^{220}_{86} Rn) = 220.01137 \; u$
$m(^{216}_{84} Po) = 216.00189 \; u$
$m(^{4}_{2} He) = 4.002603 \; u$

What is radioactivity?

$A$ radioactive element $_{90}X^{238}$ decays into $_{83}Y^{222}$. The number of $\beta$-particles emitted is:

An isotope of the original nucleus can be formed in a radioactive decay,with the emission of which of the following particles?

$A$ sample of a radioactive nucleus $A$ disintegrates to another radioactive nucleus $B$,which in turn disintegrates to some other stable nucleus $C$. Plot a graph showing the variation of the number of atoms of nucleus $B$ versus time:
(Assume that at $t=0$,there are no $B$ atoms in the sample)