The atomic number of a radioactive element increases by one unit in:

The number of $\beta$-particles emitted in the radioactive decay process $_{92}U^{238} \to _{82}Pb^{206} + x(_{2}He^{4}) + y(_{-1}e^{0})$ is:

$A$ radium $_{88}Ra^{224}$ isotope,on emission of an $\alpha$-particle,gives rise to a new element whose mass number and atomic number will be:

An atom has a mass number of $232$ and an atomic number of $90$. How many $\alpha$-particles should it emit after the emission of two $\beta$-particles,so that the resulting atom has a mass number of $212$ and an atomic number of $82$?

Which of the following processes does not occur via $\alpha$-decay?

Of the following radiations,the one most easily stopped by air is