Which of the following is used as a moderator in nuclear reactors? a) Uranium b) Radium c) Thorium d) Graphite Answer: d
The Sun’s energy is primarily due to: a) Atomic bomb reactions b) Hydrogen bomb detonation c) Nuclear fusion d) Combustion Answer: c
What is “heavy water” used in nuclear reactors? a) Water rich in minerals b) Ozonized water c) Water with heavy metal ions d) Water containing heavy hydrogen isotopes Answer: d
The radiant energy of the Sun is generated by: a) Disintegration b) Nuclear fission c) Nuclear fusion d) Combustion Answer: c
In nuclear reactors, neutrons are slowed down by the: a) Fissionable material b) Moderator c) Control rods d) Coolant system Answer: b
The massive energy of the Sun is generated by: a) Fission of uranium b) Fusion of hydrogen nuclei into helium c) Fusion of deuterium and tritium d) Fission of tritium into helium Answer: b
Alpha particles are: a) Twice as massive as beta particles b) Negatively charged particles c) Similar to helium nuclei d) Weaker in ionizing power than gamma rays Answer: c
The main reason for the Sun’s energy is: a) Nuclear fission b) Radioactivity c) Heat d) Nuclear fusion Answer: d
The radiation that penetrates deepest into the human body is: a) Ultraviolet radiation b) Alpha particles c) Beta particles d) Gamma rays Answer: d
What happens during nuclear fusion? a) A heavy nucleus splits after neutron bombardment b) A heavy nucleus spontaneously breaks apart c) Two light nuclei combine to form a heavier nucleus d) A light nucleus spontaneously breaks apart Answer: c
Which isotope of uranium is used in atomic reactors? a) U-235 b) U-236 c) U-237 d) U-232 Answer: a
In a nuclear reactor, heavy water is used to: a) Transfer heat from the reactor b) Provide high-speed neutrons c) Slow down fast neutrons d) Increase the speed of neutrons Answer: c
Which of the following can absorb neutrons and control chain reactions in nuclear fission? a) Boron b) Heavy water c) Uranium d) Plutonium Answer: a
Which of the following is a thermonuclear reaction? a) 92U238 + 0n1 → 93N239 + -1e0 b) 1H1 + 1H1 → 2He4 + 2(+1e0) c) 92U238 + 6C12 → 98Cf246 + 40n1 d) 13Al27 + 2He4 → 15P30 + 0n1 Answer: b
Another commonly used moderator in nuclear reactors is: a) Thorium b) Graphite c) Cesium d) Radium Answer: b
Which element belongs to the 4n radioactive series? a) Pb-206 b) Pb-207 c) Pb-208 d) Pb-209 Answer: c
Which radiation is not emitted during natural radioactivity? a) Alpha rays b) Beta rays c) Gamma rays d) Cathode rays Answer: d
If an element X emits one alpha and two beta particles in three steps, the final product is: a) An isobar of X b) An isotope of X c) X itself d) An isotone of X Answer: b
Which of the following has the lowest penetration power? a) Alpha rays b) Beta rays c) Gamma rays d) Delta rays Answer: a
An isobar of a nuclide is formed by: a) One alpha emission b) One beta emission c) One alpha + one beta emission d) Two alphas + two betas emission Answer: b
U-235 belongs to which radioactive decay series? a) Thorium series b) Actinium series c) Uranium series d) Neptunium series Answer: b
The loss of a beta particle results in: a) Increase of one proton b) Decrease of one neutron c) Both a and b d) None of these Answer: c
