Radioactivity
PHXII13:NUCLEI

363991 A radioactive sample of half life 10 days contains 1000\(x\) nuclei. Number of original nuclei present after 5 days is

1 \(707x\)
2 \(750x\)
3 \(500x\)
4 \(250x\)
PHXII13:NUCLEI

363992 A radioactive nucleus is being produced at a constant rate \(\alpha \) per second. Its decay constant is \(\lambda .\) If \({N_0}\) are the number of nuclei at time \(t = 0,\) then maximum number of nuclei possible are

1 \({N_0}\,\frac{\alpha }{\gamma }\)
2 \(\frac{\alpha }{\lambda }\)
3 \(\,\frac{\gamma }{\alpha } + {N_0}\)
4 \({N_0}\)
PHXII13:NUCLEI

363993 Two radioactive substances \(A\) and \(B\) have decay constants \(5\lambda \) and \(\lambda \) respectively. At \(t = 0\) they have the same number of nuclei. The ratio of number of nuclei of \(A\) to those of \(B\) will be \({\left( {\frac{1}{e}} \right)^2}\) after a time interval

1 \(\frac{1}{{4\lambda }}\)
2 \(\frac{1}{{2\lambda }}\)
3 \(2\lambda \)
4 \(4\lambda \)
PHXII13:NUCLEI

363994 A radioactive substance contains 10,000 nuclei and its half - life period is 20 days. The number of nuclei present at the end of 10 days is

1 \(7070\)
2 \(9000\)
3 \(8000\)
4 \(7500\)
PHXII13:NUCLEI

363991 A radioactive sample of half life 10 days contains 1000\(x\) nuclei. Number of original nuclei present after 5 days is

1 \(707x\)
2 \(750x\)
3 \(500x\)
4 \(250x\)
PHXII13:NUCLEI

363992 A radioactive nucleus is being produced at a constant rate \(\alpha \) per second. Its decay constant is \(\lambda .\) If \({N_0}\) are the number of nuclei at time \(t = 0,\) then maximum number of nuclei possible are

1 \({N_0}\,\frac{\alpha }{\gamma }\)
2 \(\frac{\alpha }{\lambda }\)
3 \(\,\frac{\gamma }{\alpha } + {N_0}\)
4 \({N_0}\)
PHXII13:NUCLEI

363993 Two radioactive substances \(A\) and \(B\) have decay constants \(5\lambda \) and \(\lambda \) respectively. At \(t = 0\) they have the same number of nuclei. The ratio of number of nuclei of \(A\) to those of \(B\) will be \({\left( {\frac{1}{e}} \right)^2}\) after a time interval

1 \(\frac{1}{{4\lambda }}\)
2 \(\frac{1}{{2\lambda }}\)
3 \(2\lambda \)
4 \(4\lambda \)
PHXII13:NUCLEI

363994 A radioactive substance contains 10,000 nuclei and its half - life period is 20 days. The number of nuclei present at the end of 10 days is

1 \(7070\)
2 \(9000\)
3 \(8000\)
4 \(7500\)
PHXII13:NUCLEI

363991 A radioactive sample of half life 10 days contains 1000\(x\) nuclei. Number of original nuclei present after 5 days is

1 \(707x\)
2 \(750x\)
3 \(500x\)
4 \(250x\)
PHXII13:NUCLEI

363992 A radioactive nucleus is being produced at a constant rate \(\alpha \) per second. Its decay constant is \(\lambda .\) If \({N_0}\) are the number of nuclei at time \(t = 0,\) then maximum number of nuclei possible are

1 \({N_0}\,\frac{\alpha }{\gamma }\)
2 \(\frac{\alpha }{\lambda }\)
3 \(\,\frac{\gamma }{\alpha } + {N_0}\)
4 \({N_0}\)
PHXII13:NUCLEI

363993 Two radioactive substances \(A\) and \(B\) have decay constants \(5\lambda \) and \(\lambda \) respectively. At \(t = 0\) they have the same number of nuclei. The ratio of number of nuclei of \(A\) to those of \(B\) will be \({\left( {\frac{1}{e}} \right)^2}\) after a time interval

1 \(\frac{1}{{4\lambda }}\)
2 \(\frac{1}{{2\lambda }}\)
3 \(2\lambda \)
4 \(4\lambda \)
PHXII13:NUCLEI

363994 A radioactive substance contains 10,000 nuclei and its half - life period is 20 days. The number of nuclei present at the end of 10 days is

1 \(7070\)
2 \(9000\)
3 \(8000\)
4 \(7500\)
PHXII13:NUCLEI

363991 A radioactive sample of half life 10 days contains 1000\(x\) nuclei. Number of original nuclei present after 5 days is

1 \(707x\)
2 \(750x\)
3 \(500x\)
4 \(250x\)
PHXII13:NUCLEI

363992 A radioactive nucleus is being produced at a constant rate \(\alpha \) per second. Its decay constant is \(\lambda .\) If \({N_0}\) are the number of nuclei at time \(t = 0,\) then maximum number of nuclei possible are

1 \({N_0}\,\frac{\alpha }{\gamma }\)
2 \(\frac{\alpha }{\lambda }\)
3 \(\,\frac{\gamma }{\alpha } + {N_0}\)
4 \({N_0}\)
PHXII13:NUCLEI

363993 Two radioactive substances \(A\) and \(B\) have decay constants \(5\lambda \) and \(\lambda \) respectively. At \(t = 0\) they have the same number of nuclei. The ratio of number of nuclei of \(A\) to those of \(B\) will be \({\left( {\frac{1}{e}} \right)^2}\) after a time interval

1 \(\frac{1}{{4\lambda }}\)
2 \(\frac{1}{{2\lambda }}\)
3 \(2\lambda \)
4 \(4\lambda \)
PHXII13:NUCLEI

363994 A radioactive substance contains 10,000 nuclei and its half - life period is 20 days. The number of nuclei present at the end of 10 days is

1 \(7070\)
2 \(9000\)
3 \(8000\)
4 \(7500\)