If the radioactive decay constant of radium is $1.07 \times {10^{ - 4}}$ per year, then its half life period is approximately equal to .........$years$
$8900$
$7000$
$6476$
$2520$
Starting with a sample of pure ${}^{66}Cu,\frac{7}{8}$ of it decays into $Zn$ in $15\, minutes$. The corresponding half life is..........$minutes$
Half life of a radioactive substance is $T$. The time taken for all the nuclei to disintegrate will be
The count rate for $10\ g$ of radioactive material was measured at different times and this has been shown in the graph with scale given. The half life of the material and the total count in the first half value period respectively are
Radioactive element decays to form a stable nuclide, then the rate of decay of reactant $\left( {\frac{{dN}}{{dt}}} \right)$ will vary with time $(t) $ as shown in figure
Three fourth of the active decays in a radioactive sample in $3/4\, sec$. The half life of the sample is