1. Which one of the following pairs is not correctly matched :
(a) Discovery of Meson – Hideki Yukawa
(b) Discovery of Positron and U.F. Hess – C.D. Anderson
(c) Theory of energy production in the sun and stars – H.A. Bethe
(d) Synthesis of transuranic elements – Enrico Fermi
Ans. (d) Synthesis of transuranic elements – Enrico Fermi
In 1935, Hideki Yukawa from Japan discovered Meson particles. In 1932, C.D.
Anderson and U.F. Hess found Positron, which is the opposite of the electron.
In 1938, Hans Albrecht Bethe explained how stars like the Sun get their energy.
Glenn T. Seaborg tried to make a transuranic element in 1934, but was not successful like Enrico Fermi.
2. Which one of the following is not correct :
(a) The theory of evolution was propounded by Charles Darwin.
(b) The breaking apart of the nucleus of an atom is called fusion.
(c) ‘Dry ice’ is nothing but solid carbon dioxide.
(d) Telephone was invented by Graham Bell.
Ans. (b) The breaking apart of the nucleus of an atom is called fusion.
Option (b) is incorrect. The splitting apart of an atom’s nucleus is called fission, not fusion.
Fission is when the nucleus of an atom divides into smaller pieces.
3. Read the following statements–
Statement (A): Ernest Rutherford said in the Royal Society that a man will never be able to get nuclear energy. Reason (R): He was confident that the Law of Einstein would fail and the volume would not be converted to energy.
Select your answer in the code given below :
(a) Both (A) and (R) are true and (A) is the correct explanation of (A).
(b) Both (A) and (R) are true but (R) is not the correct explanation of (A).
(c) (A) is correct but (R) is not correct.
(d) (R) is correct but (A) is not correct.
Gunter Nimtz and Alfons Stahlhofen, two physicists from the University of Koblenz in Germany, said they sent microwave photons faster than the speed of light.
This goes against a major part of Einstein’s special theory of relativity, which says that nothing can ever be faster than the speed of light.
A scintillation counter is a device that can detect and measure radiation by using a scintillator material that is excited by the radiation and then detects the resulting flashes of light.
The sun produces energy in its core by combining hydrogen atoms into helium atoms through nuclear fusion.
This energy then moves out of the core and throughout the solar system.
This is the main source of energy for the sun and stars.
Additionally, the gravitational force of stars is also a source of energy.
12. Consider the following statements: In a nuclear reactor, a self-sustained chain reaction is possible, because :
1. More neutrons are released in each of the fusion reactions. 2. The neutrons immediately take part in the fission process. 3. The fast neutrons are slowed down by graphite. 4. Every neutron released in the fission reaction initiates further fission.
Which of these statements are correct?
(a) 1, 2, and 3
(b) 1 and 3
(c) 2 and 4
(d) 2, 3 and 4
A nuclear reactor is a machine that starts and keeps nuclear reactions going.
It is used to make electricity and make ships move.
14. Which statement is not associated with nuclear fission:
(a) Neutron-induced nuclear reaction.
(b) Energy generation in stars.
(c) Source of energy in a nuclear reactor that produces electricity.
(d) Enormous energy is released in an atom bomb.
Nuclear fission is when a large atomic nucleus splits into pieces of the same size and releases a lot of energy.
Nuclear fusion is when two or smaller atoms come together to form a bigger one and also release a lot of energy.
Nuclear reactions, nuclear reactors for electricity, and atomic bombs all use nuclear fission, while the energy that stars produce comes from nuclear fusion.
15. Consider the following statements about nuclear fusion reactors :
i. They work on the principle of fission of heavy nuclei. ii. They usually have Tokamak design. iii. They operate at very high temperature.
Of these
(a) Only i and iii are correct
(b) Only i and ii are correct
(c) Only ii and iii are correct
(d) All the three i, ii and iii are correct
Nuclear fusion reactors do rely on the joining of two light nuclei.
Most nuclear fusion reactors are made in a Tokamak design.
16. The difference between a nuclear reactor and atom bomb is that :
(a) There is no chain reaction in nuclear reactor whereas this happens in atom bomb
(b) The chain reaction in nuclear reactor is controlled
(c) The chain reaction in nuclear reactor is not controlled
(d) Atom bomb is based on nuclear fusion whereas in nuclear reactor, nuclear fssion occurs.
Ans. (b) The chain reaction in nuclear reactor is controlled
In nuclear reactors, the reaction is slowed down and managed so it can be used for peaceful purposes, whereas in atomic bombs, the reaction is not managed and is not controlled.
17. With reference to the radioactivity, which of the following statements is/are correct?
1. Radioactivity is a nuclear property. 2. Hydrogen bomb is prepared on the principle of nuclear fission.
Select the correct answer using the codes given below.
Codes :
(a) Only 1
(b) Only 2
(c) Both 1 and 2
(d) Neither 1 nor 2
A report from India’s Department of Atomic Energy states that India has an abundance of thorium, with around 10.7 million tons of monazite containing 963,000 tons of thorium oxide.
Andhra Pradesh alone holds about 35% of India’s thorium reserves.
20. To meet its rapidly growing energy demand, some opine that India should pursue research and development on thorium as the future fuel of nuclear energy. In this context, what advantage does thorium hold over uranium?
1. Thorium is far more abundant in nature than uranium. 2. On the basis of the per unit mass of mined mineral, thorium can generate more energy compared to natural uranium. 3. Thorium produces less harmful waste compared to uranium.
Which of the statement(s) given above is/are correct?
(a) Only 1
(b) 2 and 3
(c) 1 and 3
(d) 1, 2, and 3
Radioactivity is something that happens when an atom is unstable and breaks apart, giving off energy.
Statement 1 is correct, but statement 2 is wrong because the hydrogen bomb is made using nuclear fusion, which is when two hydrogen atoms join together to form an atom of helium in very high temperatures.
29. The working principle of atom bomb is nuclear fission of uranium and the working principle of hydrogen bomb is –
(a) nuclear fusion of deuterium.
(b) nuclear fission of thorium.
(c) explosion of a bomb involving hydrogen gas
(d) explosion involving dynamite and T.N.T.
The hydrogen bomb has a massive amount of blasting strength that comes from a chain reaction that can’t be stopped and continues on its own.
This reaction happens when two forms of hydrogen (deuterium and tritium) come together under extremely high heat and pressure, forming helium in a process called nuclear fusion.
30. The hydrogen bomb is based on the principle of –
Edward Teller was a very famous scientist of the 20th century and was nicknamed the “father of the hydrogen bomb”. He was born in Hungary in January 1908.
In November 1952, the US tested its first nuclear fusion bomb (hydrogen bomb) at Eniwetok in the Marshall Islands.
32. Enriched Uranium is –
(a) Uranium sticks laid in the particular shell.
(b) Natural uranium in which radioactive U235 isotope is increased artificially.
(c) mixture of natural uranium and thorium.
(d) chromium-coated uranium sticks.
t1/2 = 5 years
20 years = 20/5 = 4 × t1/2
after 4 × t1/2 the remaining quantity is
= (1/2)4 = 1/16
36. The half-life of a radioactive substance is 10 days; it means there will be :
(a) complete decay of substance in 20 days
(b) complete decay of substance in 40 days
(c) decay of 3/4 part of substance in 20 days
(d) decay of 1/4 part of substance in 5 days
Ans. (c) decay of 3/4 part of substance in 20 days
The half life of a radioactive substance is 10 days; it means in next 10 days there will be half of the remaining radioactive substance. Thus, in total 20 days, there will be decay of 75% or 3/4 part of the substance.
[1/2 + 1/4 = 3/4]
37. Which one of the following is not radioactive?
Zirconium has an atomic number of 40, which means it is not a radioactive element.
Generally, elements with an atomic number higher than 80 are considered radioactive, except Technetium and Promethium, which both have an atomic number less than 80 but are still radioactive.
Therefore, Astatine (atomic number 85) and Francium (atomic number 87) are both radioactive elements, while Tritium is a radioactive version of hydrogen.
38. Which Uranium isotope is used in nuclear power plants to produce electricity?
Radioactive elements have an unstable nucleus which causes them to give off alpha, beta, and gamma rays that cannot be seen by the naked eye.
This radiation helps them to become a more stable element.
41. What happens if the control rods are not used in a nuclear reactor?
(a) The reactor will stop working
(b) Chain process would go out of bounds.
(c) The reactor will be slow to act.
(d) The reactor will continue to work as it is.
In India, most nuclear reactors (Pressurized Heavy Water Reactors – PHWRs) use natural uranium as fuel, which is primarily composed of Uranium-238 with about 0.7% Uranium-235 (the fissile isotope).
47. Kalpakkam is famous–
(a) Due to nuclear power plant
(b) Due to defense laboratory
(c) Due to rocket launching center
(d) Due to space center.
Kalpakkam (Tamil Nadu) is famous for its Madras Atomic Power Station (MAPS) and the Indira Gandhi Centre for Atomic Research (IGCAR), where India developed and operates fast breeder reactors.
It is India’s first nuclear power station built entirely by Indians.
Kalpakkam is home to India’s first pressurized (light) water reactor, which was developed by BARC and has a capacity of 80 MW.
This reactor was the land-based prototype for India’s nuclear submarines.
48. The Indira Gandhi Atomic Research Centre is located in –
(a) Maharashtra
(b) Tamil Nadu
(c) Uttar Pradesh
(d) Karnataka
The Indira Gandhi Centre for Atomic Research (IGCAR) was founded in 1971 in Kalpakkam, which is 80 kilometres south of Chennai (formerly known as Madras).
It is the second largest research facility of the Department of Atomic Energy after the Bhabha Atomic Research Centre.
49. The fuel used in the Fast Breeder Test Reactor at Kalpakkam is –
The Fast Breeder Test Reactor at Kalpakkam has been running experiments since 1985.
It uses uranium and plutonium mixed carbide fuel and liquid sodium as a cooling system.
The sodium helps to remove the heat from the core and transport it to an electrical generator.
52. Which one of the following is not correctly matched?
(a) Indira Gandhi Centre for Atomic Research – Kalpakkam
(b) Atomic Minerals Directorate for Exploration and Research – Hyderabad
(c) Harishchandra Research Institute – Chennai
(d) Saha Institute of Nuclear Physics – Kolkata
Heavy water (deuterium oxide, D₂O) is produced in India by the Heavy Water Board (HWB) Mumbai, under the Department of Atomic Energy.
The first and primary manufacturing facility is located in Trombay, Maharashtra.
Other heavy water plants are also operational in locations like Kota (Rajasthan), Baroda (Gujarat), Tuticorin (Tamil Nadu), and Thal (Maharashtra).
55. Match List-I with List-II and select the correct answer by using the codes given below : List-I List –II (Atomic Power Station) (State of Situation) A. Kalpakkam 1. Uttar Pradesh B. Narora 2. Gujarat C. Kakrapara 3. Tamil Nadu D. Trombay 4. Maharashtra Code : A B C D
Kalpakkam is a small town in Tamil Nadu that is well known for its nuclear power plants and research facilities.
Narora is situated on the bank of the Ganges river in Bulandshahar district, Uttar Pradesh and it is recognized for its nuclear power station.
The Kakrapara atomic power station is located near the city of Vyara (close to Surat) in Gujarat and is a nuclear power plant.
Trombay is a northern suburb of Mumbai, India and it is famous for the Bhabha Atomic Research Centre (BARC).
56. Which one of the following is not correctly matched?
(a) Rajasthan Atomic Power Station – Udaipur
(b) Narora Atomic Power Station – Uttar Pradesh
(c) Madras Atomic Power Plant – Kalpakkam
(d) Kaiga Atomic Power Plant – Karnataka
The only option that does not match correctly is (a) because the Rajasthan Atomic Power Station is located in Rawatbhata, Kota, Rajasthan and not in Udaipur.
57. The atomic power plants are located at Select the correct answer from the codes given below: 1. Narora
2. Ghatshila 3. Kalpakkam
4. Nangal
The Narora and Kalpakkam Power Plants both contain atomic energy.
The Madras Atomic Power Station (MAPS) is close to Chennai and was made completely in India.
It has two units that both produce 220 MW.
The Narora Atomic Power Station, located in Bulandshahar, Uttar Pradesh, also has two units that each produce 220 MW. So option (b) is the correct answer.
58. Which one of the following atomic plants of India is located in the IV Seismic Zone?
At Kudankulam in Tirunelveli, Tamil Nadu, two 1000 MW reactors based on Russian technology (known as PWR-VVER) have been set up as part of phase one of the project.
Four more reactors are planned in accordance with the agreement between India and Russia from 2008.
Currently, two of these 1000 MW reactors are up and running.
Units 3 and 4 are planned to become operational in 2023, with units 5 and 6 being constructed in 2021 and aiming to be ready by 2026-2027.
61. The function of heavy water in a nuclear reactor is to
(a) Slow down the speed of neutrons.
(b) Increase the speed of neutrons.
(c) Cool down the reactor.
(d) Stop the nuclear reaction.
Heavy water, also known as deuterium oxide (D2O), is used in nuclear reactors to slow down the speed of fast-moving neutrons.
Nuclear fission in a reactor can cause a chain reaction, so the speed of the neutrons needs to be controlled so the reaction doesn’t get out of control.
63. Which one of the following is used as a moderator in the nuclear reactor?
(a) Thorium
(b) Graphite
(c) Radium
(d) Ordinary water
Graphite is used in nuclear reactors to reduce the speed of neutrons which are created from splitting Uranium-235 atoms.
This helps to maintain the chain reaction by increasing the chances of the neutrons reacting with the Uranium-235 nucleus.
65. A fast breeder reactor is a nuclear reactor which produces electricity –
(a) By fusion process
(b) With the help of solar cells
(c) By burning phenyl substances used by it and by its reproduction
(d) By using refned hard water
A fast breeder reactor is a nuclear reactor that generates electricity through the splitting of atoms. This type of reactor produces more atoms than it uses.
66. A breeder reactor is that which –
(a) Does not require fissionable material at all
(b) Uses only heavy water
(c) Produces more fissionable material than it burns
(d) None of these
Ans. (c) Produces more fissionable material than it burns
A breeder reactor is a type of nuclear reactor that creates more fuel than it uses to produce energy.
It is designed to extend the amount of nuclear fuel available for making electricity.
67. The Nuclear Power Corporation of India is now in a position to sell “Pressurised Heavy Water Reactors” (PHWRs) to other countries.’ The reactors in question would be of capacity
(a) 200 MW or 500 MW
(b) 240 MW or 540 MW
(c) 220 MW or 500 MW
(d) 440 MW or 700 MW
The Nuclear Power Corporation of India (NPCIL) can now offer Pressurised Heavy Water Reactors (PHWRs) of 220 MW or 540 MW to other countries.
This was announced by the chair of the Atomic Energy Commission, Mr. Srikumar Banerjee, at the 54th International Atomic Energy Agency meeting in Vienna in 2010.
68. Which of the following nuclear power plants has the highest total installed capacity?
Kudankulam is the biggest nuclear power station in India with 2000 MW of installed capacity.
Kaiga Atomic Power Station has four, smaller CANDU plants of 220 MW each, giving it a total of 880 MW.
Tarapur atomic power station has 1400 MW, and Kakarapar atomic power station has two 220 MW pressurized water reactors with heavy water as a moderator, making it equal to 440 MW.
All these nuclear power plants are run by NPCIL (Nuclear Power Corporation of India Ltd).
69. The percentage of nuclear energy in India’s total energy generation is –
In India, nuclear power is the fourth biggest source of energy after thermal, hydroelectric and renewable sources.
During the specified period, nuclear energy accounted for about 3% of India’s total energy production.
As of February 28, 2022, India has 22 nuclear reactors with a total capacity of 6780 MW, which is only 1.71% of the country’s total energy generating capacity.
70. The official code name of the Pokhran nuclear test 1974, was –
India conducted five nuclear bomb tests in 1998 in the Pokhran test range of the Indian Army.
This operation was named “Shakti” and was known as Pokhran-II.
It was the second such test by India, the first being Pokhran-I.
72. ‘Operation Shakti’-98 is the name :
(a) Given to the nuclear test carried out at Pokharan in 1998
(b) Given to air exercises carried out by Indian Air Force SU-30 planes
(c) Given to the pro-active program of the Union Home Minister to contain terrorism in J&K
(d) Given to military action against terrorists in Tripura
In August 1999, the National Security Advisory Board (NSAB) created the first version of India’s Nuclear Doctrine.
This doctrine includes all the choices mentioned.
75. Consider the following statements :
1. The Nuclear Security Summits are periodically held under the aegis of the United Nations. 2. The International Panel on Fissile Materials is an organ of the International Atomic Energy Agency.
Which of the statements given above is/are correct?
(a) 1 only
(b) 2 only
(c) Both 1 and 2
(d) Neither 1 nor 2
In 2009, President Obama announced a plan to hold a summit to make sure all nuclear materials were protected worldwide within four years.
This plan led to four summits total – one in Washington D.C. in 2010, one in South Korea in 2012, one in the Netherlands in 2014, and one in Washington D.C. again in 2016.
In January 2006, the International Panel on Fissile Materials was founded.
This group of arms control and non-proliferation experts represented both nuclear weapon and non-nuclear weapon states.
76. Assertion (A): CERN (European Organization for Nuclear Research) is the world’s largest particle Physics Laboratory. Reason (R): CERN is a French acronym for the name of the provisional body founded 2 years before the organization came into existence.
Code :
(a) Both (A) and (R) are individually true, and (R) is the correct explanation of (A).
(b) Both (A) are (R) are individually true, but (R) is not the correct explanation of (A).
(c) (A) is true, but (R) is false.
(d) (A) is true, but (R) is true.
Ans. (b) Both (A) are (R) are individually true, but (R) is not the correct explanation of (A)
The European Organization for Nuclear Research (CERN) was founded in 1954 and is located in a north-western suburb of Geneva on the French-Swiss border.
CERN is the world’s largest particle physics laboratory.
The name of the organization was created in 1952, two years prior to its establishment.
77. In which one of the following locations is the International Thermonuclear Experimental Reactor (ITER) project to be built?
ITER (which means ‘The Way’ in Latin) is an experiment meant to show that fusion is an energy source that can be used.
It is being built in France with the help of seven countries – China, the European Union, India, Japan, South Korea, Russia and the United States.
This is the biggest fusion reactor ever made.
ITER won’t actually make electricity, but it will help answer important questions to make fusion usable in the future.
78. India is an important member of the ‘International Thermonuclear Experimental Reactor’. If this experiment succeeds, what is the immediate advantage for India?
(a) It can use thorium in place of uranium for power generation
(b) It can attain a global role in satellite navigation
(c) It can drastically improve the efficiency of its fission reactors in power generation
(d) It can build fusion reactors for power generation
Ans. (d) It can build fusion reactors for power generation
ITER is a research fusion reactor that is currently being built in Cadarache, France.
It is a step towards the potential of producing electricity from fusion energy, which is how the sun and stars create energy by combining hydrogen atoms.
79. Consider the following statements :
Assertion (A): India’s nuclear policy incorporates its unpreparedness to open its nuclear plants to international inspection. Reason (R): India will not produce any nuclear bomb.
Select your answer from the code given below :
(a) Both (A) and (R) are true, and (R) is the correct explanation of (A).
(b) Both (A) and (R) are true, but (R) is not the correct explanation.
(c) (A) is true, but (R) is false.
(d) (A) is false, but (R) is true.
India is not willing to let other countries look at their nuclear plants due to concerns about other nations check India’s technology secrets.
However, India has not ruled out the possibility of building nuclear weapons.
80. India has refused to sign the treaty on non-proliferation of nuclear weapons.
(a) It is discriminatory.
(b) It will slack India’s nuclear military capability.
(c) It is against the peaceful use of nuclear power.
(d) This strength negatively affects the balance in the South Asian region.
The NPT has two types of members – Nuclear Weapon states and Non-Nuclear Weapon states.
Only five countries that had tested a nuclear device before 1967 were given the status of Nuclear Weapon states.
Other countries wanting to join the NPT had to do so as Non-Nuclear Weapon states.
India tested its first nuclear device in 1974, meaning that the only way it could join the NPT was as a Non-Nuclear Weapon state.
This doesn’t allow India to keep even a small nuclear deterrent, which India feels is discriminatory.
81. Consider the following countries :
1. China
2. France 3. India
4. Israel 5. Pakistan
Which among the above are Nuclear Weapons States as recognized by the Treaty on the Non-Proliferation of Nuclear Weapons, commonly known as the Nuclear Non-Proliferation Treaty (NPT)?
(a) 1 and 2 only
(b) 1, 3, 4 and 5 only
(c) 2, 4 and 5 only
(d) 1, 2, 3, 4 and 5
The Nuclear Nonproliferation Treaty (NPT) was made in 1970 to stop the growth of nuclear weapons.
All countries involved in the treaty are split into two groups: Nuclear Weapon States (NWS) (the US, Russia, China, France, and the UK) and Non-Nuclear Weapon States (NNWS).
The five NWS pledge to reduce nuclear weapons, while the NNWS promise not to create or acquire nuclear weapons.
82. What is/are the consequence/consequences of a country becoming a member of the ‘Nuclear Suppliers Group’?
1. It will have access to the latest and most efficient nuclear technologies. 2. It automatically becomes a member of “The Treaty on the Non-Proliferation of Nuclear Weapons (NPT)”.
Which of the statements given above is/are correct?
(a) 1 only
(b) 2 only
(c) Both 1 and 2
(d) Neither 1 nor 2
At the present time, the Nuclear Suppliers Group consists of 48 countries. Iran is not one of them.
NSG was formed in response to India’s first nuclear weapon test in May 1974.
The test was conducted in Pokhran, Rajasthan, under the code name “Smiling Buddha”
48 NSG Members
84. Which country was the first, after the ban on India was lifted by the Nuclear Suppliers Group, to sign an agreement that would allow the supply of civil nuclear technology to India?
Once the ban on India was overturned by the Nuclear Suppliers Group, France was the first country to officially agree to supply India with nuclear technology for civilian use.
85. In the Indian context, what is the implication of ratifying the ‘Additional Protocol’ with the ‘International Atomic Energy Agency (IAEA)’?
(a) The civilian nuclear reactors come under IAEA safeguards (b) The military nuclear installations come under the inspection of the IAEA (c) The country will have the privilege to buy uranium from the Nuclear Suppliers Group (NSG) (d) The country automatically becomes a member of the NSG
Ans. (a) The civilian nuclear reactors come under IAEA safeguards
In its safeguard agreement, India consented to permit the IAEA access to certain civilian nuclear reactors where imported nuclear fuel was being utilized.
The additional protocol to safeguards agreement between the Government of India and IAEA for the application of Safeguards to Civilian Nuclear Facilities became effective on 25 July, 2014.
86. In India, why are some nuclear reactors kept under ‘IAEA Safeguards’ while others are not?
(a) Some use uranium and others use thorium
(b) Some use imported uranium and others use domestic supplies
(c) Some are operated by foreign enterprises and others are operated by domestic enterprises
(d) Some are State-owned and others are privately owned
Ans. (b) Some use imported uranium and others use domestic supplies
As of April 2025, India has 25 nuclear reactors in operation in 8 nuclear power plants.
Total installed capacity is 8,880 MW (3% of total power generation).
Some nuclear reactors are controlled by the IAEA (International Atomic Energy) as they use imported uranium.
This was also a requirement in the India-US Civilian Nuclear Deal of 2005, which states that reactors using imported fuel must be placed under IAEA safeguards.
