The decay constant for a radioactive nuclide is $1.5 \times 10^{-5} s ^{-1}$. Atomic of the substance is $60\,g$ mole $^{-1},\left( N _{ A }=6 \times 10^{23}\right)$. The activity of $1.0\,\mu g$ of the substance is $.......\,\times 10^{10}\,Bq$
$14$
$13$
$12$
$15$
At time $t=0$, a container has $N_{0}$ radioactive atoms with a decay constant $\lambda$. In addition, $c$ numbers of atoms of the same type are being added to the container per unit time. How many atoms of this type are there at $t=T$ ?
In a sample of radioactive material, what percentage of the initial number of active nuclei will decay during one mean life .......... $\%$
A freshly prepared sample of a radioisotope of half-life $1386 \ s$ has activity $10^3$ disintegrations per second. Given that In $2=0.693$, the fraction of the initial number of nuclei (expressed in nearest integer percentage) that will decay in the first $80 \ s$ after preparation of the sample is :
A radioactive substance has a half-life of $1$ year. The fraction of this material, that would remain after $5$ years will be
If $10\%$ of a radioactive material decays in $5$ days, then the amount of original material left after $20$ days is approximately ...............$\%$