A piece of bone of an animal from a ruin is found to have $^{14}C$ activity of $12$ disintegrations per minute per gm of its carbon content. The $^{14}C$ activity of a living animal is $16$ disintegrations per minute per gm. How long ago nearly did the animal die? ............$years$ (Given halflife of $^{14}C$ is $t_{1/2} = 5760\,years$ )
$1672$
$2391$
$3291$
$4453$
Half life of $B{i^{210}}$ is $5$ days. If we start with $50,000$ atoms of this isotope, the number of atoms left over after $10$ days is
Write the definition of half life of radioactive substance and obtain its relation to decay constant.
The activity $R$ of an unknown radioactive nuclide is measured at hourly intervals. The results found are tabulated as follows:
$t(h)$ | $0$ | $1$ | $2$ | $3$ | $4$ |
$R(MBq)$ | $100$ | $35.36$ | $12.51$ | $4.42$ | $1.56$ |
$(i)$ Plot the graph of $R$ versus $t$ and calculate half-life from the graph.
$(ii)$ Plot the graph of $\ln \left( {\frac{R}{{{R_0}}}} \right) \to t$ versus $t$ and obtain the value of half-life from the graph.
Which sample, $A$ or $B$ shown in figure has shorter mean-life?
The half-life of radioactive Polonium $(Po)$ is $138.6$ days. For ten lakh Polonium atoms, the number of disintegrations in $24$ hours is