1. | \({}_{7}^{13}\mathrm{N}\) | 2. | \({}_{5}^{10}\mathrm{B}\) |
3. | \({}_{4}^{9}\mathrm{Be}\) | 4. | \({}_{7}^{14}\mathrm{N}\) |
The mass of \({}_{7}^{15}\mathrm{N}\) is \(15.00011\) amu, mass of \({}_{8}^{16}\mathrm{O}\) is \(15.99492\) amu and \(m_p = 1.00783\) amu. Determine the binding energy of the last proton of \({ }_{8}^{16}\mathrm{O}\).
1. \(2.13\) MeV
2. \(0.13\) MeV
3. \(10\) MeV
4. \(12.13\) MeV
The rate of disintegration of a fixed quantity of a radioactive substance can be increased by:
1. increasing the temperature.
2. increasing the pressure.
3. chemical reaction.
4. it is not possible.
The power obtained in a reactor using \(\mathrm{U}^{235}\) disintegration is \(1000\) kW. The mass decay of \(\mathrm{U}^{235}\) per hour is:
1. \(1\) microgram
2. \(10\) microgram
3. \(20\) microgram
4. \(40\) microgram
The counting rate observed from a radioactive source at t = 0 second was 1600 counts per second and at t = 8 seconds it was 100 counts per second. The counting rate observed, as counts per second, at t = 6 seconds will be:
1. 400
2. 300
3. 200
4. 150
Half-lives of two radioactive substances A and B respectively are 20 min and 40 min. Initially, the samples of A and B have an equal number of nuclei. After 80 min the ratio of the remaining number of A and B nuclei is:
1. 1 : 16
2. 4 : 1
3. 1 : 4
4. 1 : 1
What fraction of a radioactive material will get disintegrated in a period of two half-lives?
1. whole
2. half
3. one-fourth
4. three-fourth