Power Plant Engineering MCQ Solved Paper for RRB NTPC

1. Gas cooled reactor uses following materials as moderator, and coolant
A. Graphite, CO₂
B. Graphite, air
C. Heavy water, CO₂
D. Lead, H₂
Answer : A

2. The risk of radioactive hazard is greatest in the turbine with following reactor
A. Pressurised water
B. Boiling water
C. Gas cooled
D. Liquid metal cooled
Answer : B

3. The size of the reactor is said to be critical when
A. Chain reaction can be initiated
B. It becomes uncontrollable
C. It explodes
D. It produces no power
Answer : A

4. A nuclear fission is initiated when the critical energy as compared to neutron binding energy of the atoms is
A. Same
B. More
C. Less
D. There is no such criterion
Answer : B

5. The fuel needed, with reflector in nuclear power plant, in order to generate sufficient neutrons to sustain a chain reaction, would be
A. More
B. Less
C. Same
D. Zero
Answer : B

6. Pressurised water reactor is designed
A. For boiling pi water in the core
B. To use liquid sodium metal as coolant
C. To use intermediate coolant
D. To prevent the water coolant from boiling in the core
Answer : D

7. In natural uranium, the constituents of three naturally occuring isotopes are
A. U??? = 0.006%, U??? = 0.712% and U??? = 99.282%
B. U??? = 0.712%, U??? = 0.006% and U??? = 99.282%
C. U??? = 99.282%, U??? = 0.006% and U??? = 0.712%
D. U??? = 0.006%, U??? = 99.282% and U??? = 0.712%
Answer : A

8. In triggering fission, which types of neutrons are more effective?
A. Fast
B. Slow
C. In bulk
D. Static
Answer : B

9. The breeding gain in case of thermal breeder reactor as compared to fast breeder reactor is
A. Same
B. Lower
C. Higher
D. Unity
Answer : B

10. The fast breeder reactor uses the following moderator
A. Demineralised water
B. Carbon dioxide
C. Heavy water
D. No moderator is used
Answer : D

11. In the breeder reactors the generation of new fissionable atom is
A. At the lower rate than the consumption
B. At a higher rate than the consumption
C. At an equal rate of the consumption
D. Depends on other considerations
Answer : B

12. Atomic number of an element in the periodic table represents the numbers of
A. Protons in the nucleus
B. Electrons in the nucleus
C. Neutrons in the nucleus
D. Electrons in the atom
Answer : A

13. The function of control rods in nuclear plants is to
A. Control temperature
B. Control radioactive pollution
C. Control absorption of neutron
D. Control fuel consumption
Answer : C

14. Superheated steam is generated in following reactor
A. Boiling water
B. Gas cooled
C. Pressurised water
D. All of the above
Answer : B

15. Enriched uranium may contain fissionable contents of the order of
A. 1-99 %
B. 1-25 %
C. 1-50 %
D. 1-75 %
Answer : A

16. Plutonium (Pu???) is produced
A. Artificially
B. By fission of Th???
C. When U??? is irradiated by neutrons
D. As basic raw material
Answer : C

17. Enriched uranium is one in which
A. Percentage of U??? has been artificially increased
B. Percentage of U has been artificially increased
C. Percentage of U??? has been artificially increased
D. Extra energy is pumped from outside
Answer : A

18. A pressurised water reactor employs pressurises for the following application
A. To maintain constant pressure in primary circuit under varying load
B. To Supply high pressure steam
C. To increase pressure of water in primary circuit
D. To provide sub cooled water at high pressure
Answer : A

19. The control rods in the control system of nuclear reactors are used to
A. Absorb excess neutrons
B. Control fuel consumption
C. Control temperature
D. All of these
Answer : A

20. The presence of reflector in nuclear power plants results in
A. Increased production of neutrons
B. Complete absorption of neutrons
C. Controlled production of neutrons
D. Decreased leakage of neutrons
Answer : D

21. The mass number of a substance represents the sum of total number of
A. Protons and neutrons in an atom
B. Protons and electrons in an atom
C. Neutrons and electrons in an atom
D. Protons and neutrons in a nucleus
Answer : D

22. Hydrogen is preferred as better coolant in comparison to CO? because former
A. Is lighter
B. Is inert
C. Has high specific heat
D. Is a good conductor
Answer : C

23. The predominant isotope of the naturally occuring element is
A. U???
B. U???
C. Pu???
D. Pu???
Answer : B

24. A power plant giving least running cost of production of electrical power is
A. Steam power plant
B. Gas turbine power plant
C. Hydro electric power plant
D. Nuclear power plant
Answer : D

25. Artificial radioactive isotopes find application in
A. Power generation
B. Nucleonic devices
C. Nuclear fission
D. Medical field
Answer : D

26. The material most commonly used for shielding is
A. Carbon
B. Lead
C. Concrete
D. All of these
Answer : C

27. The commonly used material for shielding is
A. Lead or concrete
B. Lead and tin
C. Graphite or cadmium
D. Thick galvanised sheets
Answer : A

28. Which of the following is the primary fuel?
A. U???
B. U
C. U???
D. Pu
Answer : B

29. Which of the following can be used as a coolant in nuclear plant?
A. Light or heavy water
B. Molten lead
C. Carbon dioxide
D. Freon
Answer : A

30. A nuclear unit becoming critical means
A. It is generating power to rated capacity
B. It is capable of generating much more than rated capacity
C. There is danger of nuclear spread
D. Chain reaction that causes automatic splitting of the fuel nuclei has been established
Answer : D

31. For economical operation of a nuclear plant
A. Used fuel should be reprocessed
B. Moderator should be used
C. Coolant should be employed
D. Control rods should be used
Answer : A

32. The following present serious difficulty in designing reactor shield
A. Alpha particles
B. Beta particles
C. Thermal neutrons
D. Fast neutrons and gamma rays
Answer : D

33. Reactors for propulsion applications are designed for
A. Any form of uranium
B. Natural uranium
C. Enriched uranium
D. Plutonium
Answer : C

34. Amongst the following, the fissionable materials are
A. U??? and Pu???
B. U??? and Pu???
C. U??? and Pu???
D. U??? and Pu???
Answer : A

35. Boiling water reactor uses the following as moderator, coolant and working fluid
A. Ordinary fluid
B. Heavy water
C. Molten lead
D. Hydrogen gas
Answer : A

36. Which is not identical for an atom and an isotope?
A. Mass number
B. Atomic number
C. Chemical properties
D. Position in periodic table
Answer : A

37. Boiling water reactor employs
A. Boiler
B. Direct cycle of coolant system
C. Double circuit system of coolant cycle
D. Multi passes system
Answer : B

38. Which of the following type of pump is used in liquid metal cooled reactor for circulation of liquid metal
A. Centrifugal
B. Axial
C. Reciprocation
D. Electromagnetic
Answer : D

39. A moderator
A. Absorbs neutrons
B. Does not absorb neutrons
C. Accelerates neutrons
D. None of these
Answer : B

40. U238 will undergo fission by
A. High energy (fast) neutrons alone
B. Low energy (slow) neutrons alone
C. Either fast or slow neutrons
D. Medium energy neutrons
Answer : A

41. Moderator in nuclear plants is used to
A. Reduce temperature
B. Extract heat from nuclear reaction
C. Control the reaction
D. Cause collision with the fast moving neutrons to reduce their speed
Answer : D

42. The most practical fuel for a thermonuclear reactor, both from economical and nuclear consideration is
A. Plutonium
B. Uranium
C. Deuterium
D. Thorium
Answer : C

43. Plutonium is produced
A. As basic raw material
B. By neutron irradiation of Uz
C. By neutron irradiation of thorium
D. Artificially
Answer : B

44. The efficiency of a nuclear power plant in comparison to conventional and nuclear consideration is
A. Higher cost of nuclear fuel
B. High initial cost
C. High heat rejection in condenser
D. Lower temperature and pressure conditions
Answer : D

45. Reactors for propulsion applications use
A. Natural uranium
B. Molten lead
C. Any form of uranium
D. Thorium
Answer : B

46. Each fission of U??? produces following number of fast neutrons per fission
A. 1 neutron
B. 3 neutrons
C. 1, 2 neutrons
D. 2 neutrons
Answer : D

47. A fast breeder reactor uses following as fuel
A. Enriched uranium
B. Plutonium
C. Thorium
D. U???
Answer : D

48. Which of the following are ferrite materials?
A. U??? and Pu???
B. U
C. U??? and Pu???
D. U??? and Th???
Answer : B

49. The most commonly used moderator in nuclear plants is
A. Heavy water
B. Concrete and bricks
C. Graphite and concrete
D. Graphite
Answer : D

50. A fission chain reaction in uranium can be developed
A. By increasing the contents of U???
B. By slowing down fast neutrons so that U??? fission continues by slow neutron
C. Both (A) and (B)
D. None of these
Answer : C