Controlled Nuclear Reaction

Q. Which of the following statements are true regarding a nuclear reactor?

1. It uses control rods usually made of cadmium to regulate the energy generation.
2. It uses moderators to slow down the neutrons while generating the energy.
3. Moderators like heavy water, are used to cool down the reactor, during the fission reaction.
4. None of the above.

Q. A atomic power reactor furnace can deliver 300 MW. The energy released due to fission of each of uranium atom $U^{238}$ is 170 MeV. The number of uranium atoms fission per hour will be

1. $5\times {10}^{15}$
2. $10\times {10}^{22}$
3. $40\times {10}^{21}$
4. $30\times {10}^{25}$

Q.

A moderator in a nuclear reactor serves to

1. accelerate neutrons

2. diminish the nuclear binding energy

3. provide fissionable isotopes

4. slow neutrons