A radioactive nuclide is produced at the constant rate of $n$ per second (say, by bombarding a target with neutrons). The expected number $N$ of nuclei in existence $t\, seconds$ after the number is $N_0$ is given by Where $\lambda $ is the decay constant of the sample

How much mass of uranium to be destroyed per minute to operate a nuclear reactor of $600\,MW$

The half-life of radioactive Polonium $(Po)$ is $138.6$ days. For ten lakh Polonium atoms, the number of disintegrations in $24$ hours is

A radioactive substance emits

A fraction $f_1$ of a radioactive sample decays in one mean life, and a fraction $f_2$ decays in one half-life.