Radioacitive nuclei $A$ and $B$ disintegrate into $C$ with half lives $T$ and $2T$. At $t = 0$, pumber of nuclei of each $A$ and $B$ is $x$. The number of nuclei of $C$ when rate of disintegration of $A$ and $B$ are equal is
$1.5x$
$125x$
$x$
$1.75x$
The half life of a radioactive element which has only $\frac{1}{{32}}$ of its original mass left after a lapse of $60\, days$ is ........$days$
A radioactive nucleus decays by two different process. The half life of the first process is $5$ minutes and that of the second process is $30\,s$. The effective half-life of the nucleus is calculated to be $\frac{\alpha}{11}\,s$. The value of $\alpha$ is $..............$
If the half life of a radioactive sample is $10\, hours$, its mean life is ..........$hours$
In a radioactive disintegration, the ratio of initial number of atoms to the number of atoms present at an instant of time equal to its mean life is
A source contains two phosphorous radio nuclides $_{15}^{32} P \left(T_{1 / 2}=14.3 d \right)$ and $_{15}^{33} P \left(T_{1 / 2}=25.3 d \right) .$ Initially, $10 \%$ of the decays come from $_{15}^{33} P$ How long one must wait until $90 \%$ do so?