147883 Decay constants of two radio-active samples $A$ and $B$ are $15 x$ and $3 x$ respectively. They have equal number of initial nuclei. The ratio of the number of nuclei left in $A$ and $B$ after a time $\frac{1}{6 x}$ is :

147884 The fraction of the initial number of radioactive nuclei which remain undecayed after half of a half-life of the radioactive sample is :

147886 A radioactive sample $S_{1}$ having the activity $A_{1}$ has twice the number of nuclei as another sample $S_{2}$ of activity $A_{2}$. If $A_{2}=2 A_{1}$, then the ratio of half- life of $S_{1}$ to the half-life of $S_{2}$ is :

147888 The masses of two radioactive substances are same and their half-life are $1 \mathrm{yr}$ and $2 \mathrm{yr}$ respectively. The ratio of their activities after 4 yr will be :

147883 Decay constants of two radio-active samples $A$ and $B$ are $15 x$ and $3 x$ respectively. They have equal number of initial nuclei. The ratio of the number of nuclei left in $A$ and $B$ after a time $\frac{1}{6 x}$ is :

147884 The fraction of the initial number of radioactive nuclei which remain undecayed after half of a half-life of the radioactive sample is :

147886 A radioactive sample $S_{1}$ having the activity $A_{1}$ has twice the number of nuclei as another sample $S_{2}$ of activity $A_{2}$. If $A_{2}=2 A_{1}$, then the ratio of half- life of $S_{1}$ to the half-life of $S_{2}$ is :

147888 The masses of two radioactive substances are same and their half-life are $1 \mathrm{yr}$ and $2 \mathrm{yr}$ respectively. The ratio of their activities after 4 yr will be :

147883 Decay constants of two radio-active samples $A$ and $B$ are $15 x$ and $3 x$ respectively. They have equal number of initial nuclei. The ratio of the number of nuclei left in $A$ and $B$ after a time $\frac{1}{6 x}$ is :

147884 The fraction of the initial number of radioactive nuclei which remain undecayed after half of a half-life of the radioactive sample is :

147886 A radioactive sample $S_{1}$ having the activity $A_{1}$ has twice the number of nuclei as another sample $S_{2}$ of activity $A_{2}$. If $A_{2}=2 A_{1}$, then the ratio of half- life of $S_{1}$ to the half-life of $S_{2}$ is :

147888 The masses of two radioactive substances are same and their half-life are $1 \mathrm{yr}$ and $2 \mathrm{yr}$ respectively. The ratio of their activities after 4 yr will be :

147883 Decay constants of two radio-active samples $A$ and $B$ are $15 x$ and $3 x$ respectively. They have equal number of initial nuclei. The ratio of the number of nuclei left in $A$ and $B$ after a time $\frac{1}{6 x}$ is :

147884 The fraction of the initial number of radioactive nuclei which remain undecayed after half of a half-life of the radioactive sample is :

147886 A radioactive sample $S_{1}$ having the activity $A_{1}$ has twice the number of nuclei as another sample $S_{2}$ of activity $A_{2}$. If $A_{2}=2 A_{1}$, then the ratio of half- life of $S_{1}$ to the half-life of $S_{2}$ is :

147888 The masses of two radioactive substances are same and their half-life are $1 \mathrm{yr}$ and $2 \mathrm{yr}$ respectively. The ratio of their activities after 4 yr will be :