Nuclear Power — Set 5
Technology · परमाणु ऊर्जा · Questions 41–50 of 50
Which country built the first nuclear-powered submarine, the USS Nautilus?
Correct Answer: B. USA
The USS Nautilus was launched in 1954 and revolutionized naval warfare with its ability to stay submerged almost indefinitely. It proved that compact nuclear reactors could be used for propulsion in ships. This was a major technological achievement of the early Cold War era.
Which radioactive isotope is used to determine the functionality of the human thyroid gland?
Correct Answer: B. Iodine-131
The thyroid gland naturally absorbs iodine, so Iodine-131 is used to diagnose and treat thyroid disorders. Small doses allow for clear imaging of the gland's activity. Higher doses are used to destroy overactive or cancerous thyroid tissue.
What is the primary function of heavy water in a CANDU or PHWR reactor?
Correct Answer: A. As a moderator
Heavy water (Deuterium Oxide) is an extremely efficient moderator that allows a reactor to run on natural (unenriched) uranium. It has a low probability of capturing neutrons, leaving them free for fission. Most of India’s nuclear reactors are of the PHWR type using this technology.
What is the term for a nuclear reaction where energy is released by combining hydrogen isotopes to form helium?
Correct Answer: B. Fusion
Nuclear fusion involves forcing light atoms together under extreme heat to form a heavier atom. This process releases vast amounts of energy and is the source of light and heat from the Sun. It is considered a potential source of clean, limitless energy for the future.
Which material is used to wrap fuel pellets into long 'fuel rods' in a reactor core?
Correct Answer: B. Zircaloy (Zirconium alloy)
Zircaloy is used because it is very strong, resists corrosion, and has a low neutron absorption cross-section. This ensures that neutrons can pass through the cladding to reach the fuel inside. Maintaining the integrity of these rods is a critical safety requirement.
Which organization in India is responsible for operating all commercial nuclear power plants?
Correct Answer: C. NPCIL
The Nuclear Power Corporation of India Limited (NPCIL) is a public sector enterprise under the Department of Atomic Energy. It handles the design, construction, and operation of nuclear power stations. NPCIL is headquartered in Mumbai.
What is the name of India's first indigenous nuclear research reactor established at Trombay?
Correct Answer: B. Apsara
Apsara reached criticality in 1956 and was the first research reactor in all of Asia. It was a pool-type reactor built with assistance from the United Kingdom. It was used for research in nuclear physics and the production of isotopes.
Which radioactive particle consists of two protons and two neutrons, identical to a helium nucleus?
Correct Answer: B. Alpha particle
Alpha particles are relatively heavy and positively charged, making them easy to stop with a single sheet of paper. They are emitted during the decay of very heavy elements like Uranium and Radium. However, they can be harmful if the alpha-emitting substance is swallowed or inhaled.
Which isotope of Thorium is found in nature and can be used to breed fuel for nuclear reactors?
Correct Answer: B. Thorium-232
Thorium-232 is the only naturally occurring thorium isotope found in large quantities. It is a 'fertile' material, meaning it can capture a neutron to eventually become fissile Uranium-233. India's monazite sands in Kerala are rich in this isotope.
What happens in a 'Meltdown' at a nuclear power plant?
Correct Answer: A. The fuel rods melt due to overheating
A meltdown occurs if the reactor's cooling system fails and the heat from fission causes the fuel to liquefy. This is a severe accident that can breach the reactor vessel and release radioactive materials. Modern reactors use multiple redundant cooling systems to prevent this from happening.