At time $t = 0, N_1$ nuclei of decay constant $\lambda _1 \,\& \,N_2$ nuclei of decay constant $\lambda _2$ are mixed . The decay rate of the mixture is :
${N_1}{N_2}{e^{ - \left( {{\lambda _1} + {\lambda _2}} \right)t}}$
$ + \left( {\frac{{{N_1}}}{{{N_2}}}} \right){e^{ - \left( {{\lambda _1} - {\lambda _2}} \right)t}}$
$ + ({N_1}{\lambda _1}{e^{ - {\lambda _1}t}} + {N_2}{\lambda _2}{e^{ - {\lambda _2}t}})$
$ + {N_1}{\lambda _1}{N_2}{\lambda _2}{e^{ - \left( {{\lambda _1} + {\lambda _2}} \right)t}}$
At $t = 0$, number of active nuclei in a sample is $N_0$. How much no. of nuclei will decay in time between its first mean life and second half life?
At any instant, two elements $X _1$ and $X _2$ have same number of radioactive atoms. If the decay constant of $X _1$ and $X _2$ are $10 \lambda$ and $\lambda$ respectively. then the time when the ratio of their atoms becomes $\frac{1}{e}$ respectively will be
The rate of disintegration of fixed quantity of a radioactive element can be increased by
A radioactive nuclei with decay constant $0.5/s$ is being produced at a constant rate of $100\, nuclei/s$. If at $t\, = 0$ there were no nuclei, the time when there are $50\, nuclei$ is
At time $t=0$, a material is composed of two radioactive atoms ${A}$ and ${B}$, where ${N}_{{A}}(0)=2 {N}_{{B}}(0)$ The decay constant of both kind of radioactive atoms is $\lambda$. However, A disintegrates to ${B}$ and ${B}$ disintegrates to ${C}$. Which of the following figures represents the evolution of ${N}_{{B}}({t}) / {N}_{{B}}(0)$ with respect to time $t$ ?
${N}_{{A}}(0)={No} . \text { of } {A} \text { atoms at } {t}=0$
${N}_{{B}}(0)={No} . \text { of } {B} \text { atoms at } {t}=0$