21. Which of the following are ferrite materials
(a) U233andPu239
(b) U
(c) U238andPu239
(d) U238andTh239
(e) none of the above
Ans: b
22. Ferrite material is
(a) the most fissionable material
(b) the basic fuel for nuclear paints
(c) basic raw material for nuclear plants
(d) the material which absorbs neutrons and undergoes spontaneous changes leading to the formation of fissionable material
(e) none of the above
Ans: d
23. Enriched uranium is one in which
(a) %age of U235 has been artificially in-creased
(b) %age of U has been artificially in¬creased
(c) %age of U234 has been artificially in-creased
(d) extra energy is pumped from outside
(e) all impurities have been removed
Ans: a
24. Which of the following particles is the lightest
(a) nucleus
(b) electron
(c) proton
(d) meson
(e) neutron
Ans: b
25. Which of the following is the heaviest
(a) neutron
(b) proton
(c) atom
(d) electron
(e) nucleus
Ans: c
26. In fast breeder reactors
(a) any type of moderator can be used
(b) graphite is used as the moderator
(c) heavy water is used as the moderator
(d) moderator may or may not be used
(e) moderator is dispensed with
Ans: e
27. In nuclear fission each neutron that causes fission releases
(a) no new neutron
(b) at least one new neutron
(c) one new neutron
(d) more than one new neutrons
(e) many-fold neutrons
Ans: d
28. The breeding gain in case of thermal breeder reactor as compared to fast breeder reactor is
(a) same
(b) lower
(c) higher
(d) unity
(e) higher/lower depending on the size of reactor
Ans: b
29. Gas cooled reactor uses following materials as moderator, and coolant
(a) graphite, C02
(b) graphite, air
(c) heavy water, C02
(d) lead, H2
(e) concrete, N2
Ans: a
30. A nuclear fission produces energy of following order in MeV
(a) 20
(b) 200
(c) 2000
(d) 20,000
(e) 2 x 105
Ans: b
31. The process by which a heavy nucleus is splitted into two light nuclei is known as
(a) splitting
(b) fission
(c) fusion
(d) disintegration
(e) chain reaction
Ans: b
32. 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
(e) none of the above
Ans: b
33. The fast breeder reactor uses the following moderator
(a) demineralised water
(b) carbon dioxide
(c) heavy water
(d) graphite
(e) no moderator is used
Ans: e
34. The first unclear power plant in India is located at
(a) Kota
(b) Kalapakkam
(c) Tarapur
(d) Baraeilly
(e) Kerala
Ans: c
35. The nuclear power plant at Tarapur has the following reactor
(a) fast breeder
(b) pressurised water
(c) boiling water
(d) sodium graphite
(e) none of the above
Ans: c
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
(e) none of the above
Ans: a
36. Ideally the neutron flux in reactor should be
(a) maximum in centre and zero at side
(b) maximum at side and zero in centre
(c) uniform throughout
(d) zero throughout
(e) none of the above
Ans: c
37. Enriched uranium may contain fissionable contents of the order of
(a) 1-99%
(b) 1-25%
(c) 1-50%
(d) 1-75%
(e) 1-90%
Ans: a
38. U235 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
(e) none of the above
Ans: c
39. 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
(e) none of the above
Ans: a
40. A reactor capable of converting a ferrite material into fissile isotopes is called
(a) regenerative reactor
(b) fast breeder reactor
(c) breeder reactor
(d) boiling water reactor
(e) ferrite reactor
Ans: a