Originally the radioactive beta decay was thought as a decay of a nucleus with the emission of electrons only (Case $I$) . However, in addition to the electron, another (nearly) massless and electrically neutral particle is also emitted (Case $II$). Based on the figure below, which of the following is correct?
$(a)$ in both cases $I$ and $II$
$(a)$ in case $I$ and $(b)$ in case $II$
$(a)$ in case $II$ and $(b)$ in case $I$
$(b)$ in both cases $I$ and $II$
A nucleus of lead $Pb _{82}^{214}$ emits two electrons followed by an $\alpha$-particle. The resulting nucleus will have
The $\beta$-particles of a radioactive metal originate from
For the given reaction, the particle $X$ is $_6{C^{11}}{ \to _5}{B^{11}} + {\beta ^ + } + X$
An element $A$ decays into element $C$ by a two step process :
$A \to B + {\;_2}H{e^4}$
$B \to C + \;2{e^ - }$
Then
Assertion : Radioactive nuclei emit ${\beta ^ - }$ particles.
Reason : Electrons exist inside the nucleus