Radioactivity
NUCLEAR PHYSICS

147659 Half life of a radioactive substance is 20 minute. Difference between points of time when it is $33 \%$ disintegrated and $67 \%$ disintegrated is approximately

1 40 minute
2 10 minute
3 15 minute
4 20 minute
NUCLEAR PHYSICS

147660 A mixture consists of two radioactive materials $A_{1}$ and $A_{2}$ with half lives of $20 \mathrm{~s}$ and $10 \mathrm{~s}$ respectively. Initially the mixture has $40 \mathrm{~g}$ of $A_{1}$ and $160 \mathrm{~g}$ of $A_{2}$. The amount of the two in the mixture will become equal after

1 $60 \mathrm{~s}$
2 $80 \mathrm{~s}$
3 $20 \mathrm{~s}$
4 $40 \mathrm{~s}$
NUCLEAR PHYSICS

147663 A nucleus of uranium decays at rest into nuclei of thorium and helium. Then :

1 the helium nucleus has less momentum than the thorium nucleus
2 the helium nucleus has more momentum than the thorium nucleus
3 the helium nucleus has less kinetic energy than the thorium nucleus
4 the helium nucleus has more kinetic energy than the thorium nucleus
NUCLEAR PHYSICS

147664 A radioactive nucleus can decay by two different processes. The half life for the first process is $t_{1}$ and that for the second process is $t_{2}$. If effective half life is $t$, then

1 $\mathrm{t}=\mathrm{t}_{1}+\mathrm{t}_{2}$
2 $\frac{1}{t}=\frac{1}{t_{1}}+\frac{1}{t_{2}}$
3 $t=\frac{2 t_{1} t_{2}}{t_{1}+t_{2}}$
4 $t=\frac{t_{1}+t_{2}}{2}$
NUCLEAR PHYSICS

147659 Half life of a radioactive substance is 20 minute. Difference between points of time when it is $33 \%$ disintegrated and $67 \%$ disintegrated is approximately

1 40 minute
2 10 minute
3 15 minute
4 20 minute
NUCLEAR PHYSICS

147660 A mixture consists of two radioactive materials $A_{1}$ and $A_{2}$ with half lives of $20 \mathrm{~s}$ and $10 \mathrm{~s}$ respectively. Initially the mixture has $40 \mathrm{~g}$ of $A_{1}$ and $160 \mathrm{~g}$ of $A_{2}$. The amount of the two in the mixture will become equal after

1 $60 \mathrm{~s}$
2 $80 \mathrm{~s}$
3 $20 \mathrm{~s}$
4 $40 \mathrm{~s}$
NUCLEAR PHYSICS

147663 A nucleus of uranium decays at rest into nuclei of thorium and helium. Then :

1 the helium nucleus has less momentum than the thorium nucleus
2 the helium nucleus has more momentum than the thorium nucleus
3 the helium nucleus has less kinetic energy than the thorium nucleus
4 the helium nucleus has more kinetic energy than the thorium nucleus
NUCLEAR PHYSICS

147664 A radioactive nucleus can decay by two different processes. The half life for the first process is $t_{1}$ and that for the second process is $t_{2}$. If effective half life is $t$, then

1 $\mathrm{t}=\mathrm{t}_{1}+\mathrm{t}_{2}$
2 $\frac{1}{t}=\frac{1}{t_{1}}+\frac{1}{t_{2}}$
3 $t=\frac{2 t_{1} t_{2}}{t_{1}+t_{2}}$
4 $t=\frac{t_{1}+t_{2}}{2}$
NUCLEAR PHYSICS

147659 Half life of a radioactive substance is 20 minute. Difference between points of time when it is $33 \%$ disintegrated and $67 \%$ disintegrated is approximately

1 40 minute
2 10 minute
3 15 minute
4 20 minute
NUCLEAR PHYSICS

147660 A mixture consists of two radioactive materials $A_{1}$ and $A_{2}$ with half lives of $20 \mathrm{~s}$ and $10 \mathrm{~s}$ respectively. Initially the mixture has $40 \mathrm{~g}$ of $A_{1}$ and $160 \mathrm{~g}$ of $A_{2}$. The amount of the two in the mixture will become equal after

1 $60 \mathrm{~s}$
2 $80 \mathrm{~s}$
3 $20 \mathrm{~s}$
4 $40 \mathrm{~s}$
NUCLEAR PHYSICS

147663 A nucleus of uranium decays at rest into nuclei of thorium and helium. Then :

1 the helium nucleus has less momentum than the thorium nucleus
2 the helium nucleus has more momentum than the thorium nucleus
3 the helium nucleus has less kinetic energy than the thorium nucleus
4 the helium nucleus has more kinetic energy than the thorium nucleus
NUCLEAR PHYSICS

147664 A radioactive nucleus can decay by two different processes. The half life for the first process is $t_{1}$ and that for the second process is $t_{2}$. If effective half life is $t$, then

1 $\mathrm{t}=\mathrm{t}_{1}+\mathrm{t}_{2}$
2 $\frac{1}{t}=\frac{1}{t_{1}}+\frac{1}{t_{2}}$
3 $t=\frac{2 t_{1} t_{2}}{t_{1}+t_{2}}$
4 $t=\frac{t_{1}+t_{2}}{2}$
NEET Test Series from KOTA - 10 Papers In MS WORD WhatsApp Here
NUCLEAR PHYSICS

147659 Half life of a radioactive substance is 20 minute. Difference between points of time when it is $33 \%$ disintegrated and $67 \%$ disintegrated is approximately

1 40 minute
2 10 minute
3 15 minute
4 20 minute
NUCLEAR PHYSICS

147660 A mixture consists of two radioactive materials $A_{1}$ and $A_{2}$ with half lives of $20 \mathrm{~s}$ and $10 \mathrm{~s}$ respectively. Initially the mixture has $40 \mathrm{~g}$ of $A_{1}$ and $160 \mathrm{~g}$ of $A_{2}$. The amount of the two in the mixture will become equal after

1 $60 \mathrm{~s}$
2 $80 \mathrm{~s}$
3 $20 \mathrm{~s}$
4 $40 \mathrm{~s}$
NUCLEAR PHYSICS

147663 A nucleus of uranium decays at rest into nuclei of thorium and helium. Then :

1 the helium nucleus has less momentum than the thorium nucleus
2 the helium nucleus has more momentum than the thorium nucleus
3 the helium nucleus has less kinetic energy than the thorium nucleus
4 the helium nucleus has more kinetic energy than the thorium nucleus
NUCLEAR PHYSICS

147664 A radioactive nucleus can decay by two different processes. The half life for the first process is $t_{1}$ and that for the second process is $t_{2}$. If effective half life is $t$, then

1 $\mathrm{t}=\mathrm{t}_{1}+\mathrm{t}_{2}$
2 $\frac{1}{t}=\frac{1}{t_{1}}+\frac{1}{t_{2}}$
3 $t=\frac{2 t_{1} t_{2}}{t_{1}+t_{2}}$
4 $t=\frac{t_{1}+t_{2}}{2}$