Power Plant Engineering Multiple Choice Questions on “Chain Reaction and Nuclear Reactors”.
1. The atomic weight and atomic number of an element are A and Z respectively. What is the number of neutrons in the atom of that element?
a) Z
b) A
c) A+Z
d) A-Z
Answer: d
Clarification: Number of neutrons = Atomic weight – Atomic number.
2. The time required for half of the __________ of a radioactive isotope to decay is called its half-life.
a) neutron
b) electron
c) proton
d) nuclei
Answer: d
Clarification: The time required for half of the nuclei of a radioactive isotope to decay is called its half life.
3. Thermal nuclear reactors using enriched uranium as fuel contains a maximum of __________ percent fissile material i.e. U-235.
a) 1
b) 2
c) 3
d) 6
Answer: c
Clarification: Thermal nuclear reactors using enriched uranium as fuel contains a maximum of 6 percent fissile material i.e. U-235.
4. __________ moderator is used in a fast breeder reactor.
a) Heavy water
b) Graphite
c) No
d) Beryllium
Answer: c
Clarification: A fast breeder reactor doesn’t employ any moderator.
5. Nuclides having the same atomic number are termed as?
a) Isobars
b) Isotones
c) Isotopes
d) Isomers
Answer: d
Clarification: Isomers are nuclides having the same atomic number.
6. Main source of __________ is monazite sand.
a) Uranium
b) Polonium
c) Halfnium
d) Thorium
Answer: d
Clarification: Thorium is the main source of Monazite Sand.
7. Emission of β-particles during radioactive decay of a substance is from __________
a) nucleus
b) innermost shell
c) outermost shell
d) none of the mentioned
Answer: a
Clarification: Emission of β-particles during radioactive decay of a substance is from the nucleus as all emissions are nuclear phenomenon.
8. A fertile material is the one, that can be __________
a) converted into fissile material on absorption of neutron
b) fissioned by either slow or fast neutrons
c) fissioned by slow (thermal) neutrons
d) fissioned by fast neutrons
Answer: a
Clarification: A fertile material is the one, which can be converted into fissile material on absorption of neutron.
9. The half-life period of a radioactive element depends on its __________
a) temperature
b) pressure
c) amount
d) none of the mentioned
Answer: d
Clarification: The half-life is independent of the mentioned factors.
10. Which is radioactive in nature?
a) Helium
b) Deuterium
c) Tritium
d) Heavy Hydrogen
Answer: c
Clarification: Tritium is a radioactive element.
11. Which is the most commonly used nuclear fuel in boiling water reactor?
a) enriched uranium
b) plutonium
c) natural uranium
d) monazite sand
Answer: a
Clarification: Enriched uranium is the most commonly used nuclear fuel in boiling water reactor.
12. Enrichment of uranium is done to increase the concentration of __________ in the natural uranium.
a) U-235
b) U-233
c) U-238
d) PU-239
Answer: a
Clarification: Enrichment of uranium is done to increase the concentration of U-235 in the natural uranium.
13. Fuel for a nuclear reactor (thermal) is _____________
a) Uranium
b) Plutonium
c) Radium
d) None of the mentioned
Answer: a
Clarification: Uranium is the fuel for a thermal reactor.
14. The first underground nuclear test was conducted by India at _____________
a) Pokhran
b) Kalpakkam
c) Jaisalmer
d) Narora
Answer: a
Clarification: Pokhran had the very first underground nuclear test.