1. | \({}_{26}^{89}\mathrm{Kr}\) | 2. | \({}_{36}^{89}\mathrm{Kr}\) |
3. | \({}_{26}^{90}\mathrm{Sr}\) | 4. | \({}_{38}^{89}\mathrm{Sr}\) |
Fusion reaction takes place at a higher temperature because:
1. | atoms get ionized at high temperatures. |
2. | kinetic energy is high enough to overcome the Coulomb repulsion between nuclei. |
3. | molecules break up at a high temperature. |
4. | nuclei break up at a high temperature. |
Which of the following is used as a moderator in nuclear reactors?
1. Plutonium
2. Cadmium
3. Heavy water
4. Uranium
1. | \(1.5\times 10^{17}\) | 2. | \(3\times 10^{19}\) |
3. | \(1.5\times 10^{25}\) | 4. | \(3\times 10^{25}\) |