A free neutron decays into a proton but a free proton does not decay into neutron. This is because
neutron is an uncharged particle
proton is a charged particle
neutron is a composite particle made of a proton and an electron
neutron has larger rest mass than proton
In gamma ray emission from a nucleus
The $\beta$-particles of a radioactive metal originate from
In the nuclear reaction $_{85}{X^{297}} \to Y + 4\alpha ,\;Y$ is
Atomic mass number of an element thorium is $232$ and its atomic number is $90$. The end product of this radioactive element is an isotope of lead (atomic mass $208$ and atomic number $82$). The number of alpha and beta particles emitted is
Statement $-1$ : A nucleus having energy $E _{1}$ decays $\beta^{-}$ emission to daughter nucleus having energy $E _{2}$ but the $\beta^{-}$rays are emitted with a continuous energy spectrum having end point energy $E _{1}- E _{2}$
Statement $-2$ : To conserve energy and momentum in $\beta$ decay at least three particles must take part in the transformation.