147793 A radioactive nucleus can decay by two different processes. Half-life for the first process is 3.0 hours while it is 4.5 hours for the second process. The effective half- life of the nucleus will be:

147794 The disintegration rate of a certain radioactive sample at any instant is 4250 disintegrations per minute. 10 minutes later the rate becomes 2250 disintegrations per minute. The approximate decay constant is:
(Take $\left.\log _{10} 1.88=0.274\right)$

147795 If $\frac{7}{8}$ part of an artificial radioactive element decays in $168 \mathrm{sec}$, its half life will be -

147796 A radioactive nucleus ${ }_{Z}^{A} X$ undergoes spontaneous decay in the sequence
${ }_{\mathrm{Z}}^{\mathrm{A}} \mathrm{X} \rightarrow{ }_{\mathrm{z}-1} \mathrm{~B} \rightarrow{ }_{\mathrm{z}-3} \mathrm{C} \rightarrow{ }_{\mathrm{z}-2} \mathrm{D}$
Where $Z$ is the atomic number of element $X$. The possible decay particles in the sequence are

147793 A radioactive nucleus can decay by two different processes. Half-life for the first process is 3.0 hours while it is 4.5 hours for the second process. The effective half- life of the nucleus will be:

147794 The disintegration rate of a certain radioactive sample at any instant is 4250 disintegrations per minute. 10 minutes later the rate becomes 2250 disintegrations per minute. The approximate decay constant is:
(Take $\left.\log _{10} 1.88=0.274\right)$

147795 If $\frac{7}{8}$ part of an artificial radioactive element decays in $168 \mathrm{sec}$, its half life will be -

147796 A radioactive nucleus ${ }_{Z}^{A} X$ undergoes spontaneous decay in the sequence
${ }_{\mathrm{Z}}^{\mathrm{A}} \mathrm{X} \rightarrow{ }_{\mathrm{z}-1} \mathrm{~B} \rightarrow{ }_{\mathrm{z}-3} \mathrm{C} \rightarrow{ }_{\mathrm{z}-2} \mathrm{D}$
Where $Z$ is the atomic number of element $X$. The possible decay particles in the sequence are

147793 A radioactive nucleus can decay by two different processes. Half-life for the first process is 3.0 hours while it is 4.5 hours for the second process. The effective half- life of the nucleus will be:

147794 The disintegration rate of a certain radioactive sample at any instant is 4250 disintegrations per minute. 10 minutes later the rate becomes 2250 disintegrations per minute. The approximate decay constant is:
(Take $\left.\log _{10} 1.88=0.274\right)$

147795 If $\frac{7}{8}$ part of an artificial radioactive element decays in $168 \mathrm{sec}$, its half life will be -

147796 A radioactive nucleus ${ }_{Z}^{A} X$ undergoes spontaneous decay in the sequence
${ }_{\mathrm{Z}}^{\mathrm{A}} \mathrm{X} \rightarrow{ }_{\mathrm{z}-1} \mathrm{~B} \rightarrow{ }_{\mathrm{z}-3} \mathrm{C} \rightarrow{ }_{\mathrm{z}-2} \mathrm{D}$
Where $Z$ is the atomic number of element $X$. The possible decay particles in the sequence are

147793 A radioactive nucleus can decay by two different processes. Half-life for the first process is 3.0 hours while it is 4.5 hours for the second process. The effective half- life of the nucleus will be:

147794 The disintegration rate of a certain radioactive sample at any instant is 4250 disintegrations per minute. 10 minutes later the rate becomes 2250 disintegrations per minute. The approximate decay constant is:
(Take $\left.\log _{10} 1.88=0.274\right)$

147795 If $\frac{7}{8}$ part of an artificial radioactive element decays in $168 \mathrm{sec}$, its half life will be -

147796 A radioactive nucleus ${ }_{Z}^{A} X$ undergoes spontaneous decay in the sequence
${ }_{\mathrm{Z}}^{\mathrm{A}} \mathrm{X} \rightarrow{ }_{\mathrm{z}-1} \mathrm{~B} \rightarrow{ }_{\mathrm{z}-3} \mathrm{C} \rightarrow{ }_{\mathrm{z}-2} \mathrm{D}$
Where $Z$ is the atomic number of element $X$. The possible decay particles in the sequence are