Law of Radioactive decay
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NUCLEAR PHYSICS

147905 A radioactive element $x$ converts into another stable element. Half-life of $x$ is $2 \mathrm{~h}$, initially only $x$ is present. After time t, the ratio of atoms of $x$ and $y$ is found to be $1: 4$, then $t$ in hour is

1 2
2 4
3 between 4 and 6
4 6
UP CPMT-2009
NUCLEAR PHYSICS

147906 The fraction of atoms of radioactive element that decays in 6 days is $7 / 8$. The fraction that decays in 10 days will be

1 $\frac{77}{80}$
2 $\frac{71}{80}$
3 $\frac{31}{32}$
4 $\frac{15}{16}$
UP CPMT-2014
NUCLEAR PHYSICS

147909 In a radioactive substance at $t=0$, the number of atoms is $8 \times 10^{4}$, its half-life period is $3 \mathrm{yr}$. The number of atoms $1 \times 10^{4}$ will remain after interval

1 $9 \mathrm{yr}$
2 $8 \mathrm{yr}$
3 $6 \mathrm{yr}$
4 $24 \mathrm{yr}$
UP CPMT-2010
NUCLEAR PHYSICS

147910 If the half-life of any sample of radioactive substance is $\mathbf{4}$ days, then the fraction of sample will remain undecayed after 2 days, will be

1 $\sqrt{2}$
2 $\frac{1}{\sqrt{2}}$
3 $\frac{\sqrt{2}-1}{\sqrt{2}}$
4 $\frac{1}{2}$
UP CPMT-2005
NEET DIGITAL LIBRARY
NUCLEAR PHYSICS

147905 A radioactive element $x$ converts into another stable element. Half-life of $x$ is $2 \mathrm{~h}$, initially only $x$ is present. After time t, the ratio of atoms of $x$ and $y$ is found to be $1: 4$, then $t$ in hour is

1 2
2 4
3 between 4 and 6
4 6
UP CPMT-2009
NUCLEAR PHYSICS

147906 The fraction of atoms of radioactive element that decays in 6 days is $7 / 8$. The fraction that decays in 10 days will be

1 $\frac{77}{80}$
2 $\frac{71}{80}$
3 $\frac{31}{32}$
4 $\frac{15}{16}$
UP CPMT-2014
NUCLEAR PHYSICS

147909 In a radioactive substance at $t=0$, the number of atoms is $8 \times 10^{4}$, its half-life period is $3 \mathrm{yr}$. The number of atoms $1 \times 10^{4}$ will remain after interval

1 $9 \mathrm{yr}$
2 $8 \mathrm{yr}$
3 $6 \mathrm{yr}$
4 $24 \mathrm{yr}$
UP CPMT-2010
NUCLEAR PHYSICS

147910 If the half-life of any sample of radioactive substance is $\mathbf{4}$ days, then the fraction of sample will remain undecayed after 2 days, will be

1 $\sqrt{2}$
2 $\frac{1}{\sqrt{2}}$
3 $\frac{\sqrt{2}-1}{\sqrt{2}}$
4 $\frac{1}{2}$
UP CPMT-2005
Join With Us for More Updates
NUCLEAR PHYSICS

147905 A radioactive element $x$ converts into another stable element. Half-life of $x$ is $2 \mathrm{~h}$, initially only $x$ is present. After time t, the ratio of atoms of $x$ and $y$ is found to be $1: 4$, then $t$ in hour is

1 2
2 4
3 between 4 and 6
4 6
UP CPMT-2009
NUCLEAR PHYSICS

147906 The fraction of atoms of radioactive element that decays in 6 days is $7 / 8$. The fraction that decays in 10 days will be

1 $\frac{77}{80}$
2 $\frac{71}{80}$
3 $\frac{31}{32}$
4 $\frac{15}{16}$
UP CPMT-2014
NUCLEAR PHYSICS

147909 In a radioactive substance at $t=0$, the number of atoms is $8 \times 10^{4}$, its half-life period is $3 \mathrm{yr}$. The number of atoms $1 \times 10^{4}$ will remain after interval

1 $9 \mathrm{yr}$
2 $8 \mathrm{yr}$
3 $6 \mathrm{yr}$
4 $24 \mathrm{yr}$
UP CPMT-2010
NUCLEAR PHYSICS

147910 If the half-life of any sample of radioactive substance is $\mathbf{4}$ days, then the fraction of sample will remain undecayed after 2 days, will be

1 $\sqrt{2}$
2 $\frac{1}{\sqrt{2}}$
3 $\frac{\sqrt{2}-1}{\sqrt{2}}$
4 $\frac{1}{2}$
UP CPMT-2005
For More Updates join with Us
NUCLEAR PHYSICS

147905 A radioactive element $x$ converts into another stable element. Half-life of $x$ is $2 \mathrm{~h}$, initially only $x$ is present. After time t, the ratio of atoms of $x$ and $y$ is found to be $1: 4$, then $t$ in hour is

1 2
2 4
3 between 4 and 6
4 6
UP CPMT-2009
NUCLEAR PHYSICS

147906 The fraction of atoms of radioactive element that decays in 6 days is $7 / 8$. The fraction that decays in 10 days will be

1 $\frac{77}{80}$
2 $\frac{71}{80}$
3 $\frac{31}{32}$
4 $\frac{15}{16}$
UP CPMT-2014
NUCLEAR PHYSICS

147909 In a radioactive substance at $t=0$, the number of atoms is $8 \times 10^{4}$, its half-life period is $3 \mathrm{yr}$. The number of atoms $1 \times 10^{4}$ will remain after interval

1 $9 \mathrm{yr}$
2 $8 \mathrm{yr}$
3 $6 \mathrm{yr}$
4 $24 \mathrm{yr}$
UP CPMT-2010
NUCLEAR PHYSICS

147910 If the half-life of any sample of radioactive substance is $\mathbf{4}$ days, then the fraction of sample will remain undecayed after 2 days, will be

1 $\sqrt{2}$
2 $\frac{1}{\sqrt{2}}$
3 $\frac{\sqrt{2}-1}{\sqrt{2}}$
4 $\frac{1}{2}$
UP CPMT-2005
NEET DIGITAL LIBRARY