The most penetrating radiation out of the following is

In a radioactive reaction $_{92}X^{232} \to _{82}Y^{204}$,the number of $\alpha$-particles emitted is:

Alpha rays emitted from a radioactive substance are

The atomic weight of thorium is $A = 232$ and the atomic number is $Z = 90$. After disintegration,the final element obtained is $Pb$,which has $A = 208$ and $Z = 82$. In this process,the number of emitted $\alpha$ and $\beta$ particles are:

$A$ positron is emitted from ${}^{23}Na_{11}$. The ratio of the atomic mass and atomic number of the resulting nuclide is

Alpha particles are