Consider following radioactive decay of
$I{:}_{92}U\stackrel{-a}{\to }{}_{90}Th$
$II{:}_{90}U\stackrel{-a}{\to }{}_{88}Ra$
In which case group of the parent and daughter element remain uncharged ?

Q. A radioactive substance (parent) decays to it's daughter element, the age of radioactive substance (t) is related to the daughter (d) parent (p) ratio by the equation :

Q. A parent nuclei (decay constant ${\lambda }_1$) forms a daughter element (decay constant ${\lambda }_2$). The nuclear change will show radioactive equilibrium if :

Q. Alkaline earth metal is radioactive. It and its daughter element decay by emitting 3 $\alpha$-particles in succession. In what group should the resulting element be formed?

Q. In a radioactive process, the atomic number of the element may or may not changed. If the parent atom undergoes successive radioactive decays : alpha, beta and gamma. How many atomic number of daughter atom is less than parent atom?