Nuclear (Physics) Part-I

Thorium is more abundant in Earth's crust than uranium, at a concentration of 0.0006% vs. 0.00018% for uranium (3 times). On the basis of per unit mass of mined mineral, thorium can generate more energy compared to natural uranium.

Thorium cycles exclusively allow thermal breeder reactors (as opposed to fast breeders). Thorium cycle does not irradiate U-238 and therefore does not produce transuranic (bigger than uranium) atoms like plutonium, americium, curium, etc.

These transuranics are the major health concern of long-term nuclear waste. Also the thorium fuel generates no new bomb-usable material in the waste profile.

Across the country, the Atomic Minerals Directorate for Exploration and Research (AMD), a constituent unit of the Department of Atomic Energy (DAE), has established a total of 3,82,675 tonnes in situ U₃O₈ in 47 uranium deposits in Andhra Pradesh, Telangana, Jharkhand, Meghalaya, Rajasthan, Karnataka, Chhattisgarh, Uttar Pradesh, Uttarakhand, Himachal Pradesh and Maharashtra, as per the data of 2022.

However, in India major production of electricity is achieved through coal-based thermal power plants, which is 48.6% of the total installed power generation capacity, as per the data of February-end, 2024. Hence, Statement-I is correct.

Uranium enriched to concentrations above 0.7% but less than 20% uranium-235 is defined as low enriched uranium (LEU). Most civil and commercial nuclear reactors use LEU that is about 3–5% uranium-235 for the production of electricity.

Uranium enriched to more than 20% uranium-235 is defined as highly enriched uranium (HEU), which can be used in nuclear weapons. All HEU is weapons-usable, but the lower the enrichment level, the greater the amount of material required to achieve a critical mass – the amount of material required to build a bomb.

States with nuclear weapons typically use so-called weapons-grade HEU, which is typically defined as 90% HEU or above, to minimize weapons’ size. Hence, Statement-II is incorrect.

Thorium, plutonium and uranium are radioactive elements which are used as a nuclear fuel. Cadmium is not a radioactive element. Cadmium rods are used as a neutron absorber in nuclear reactor control rods and shields.

Chromium is not associated with atomic power. Monazite is a primary ore of thorium which can be used as nuclear fuel. Beryllium oxide is used as moderator in nuclear reactor.

All the radioactive elements can be used as the nuclear fuel. Helium is an inert gas. It does not form compounds or react with any other element.

The most common fissile nuclear fuels are uranium-235 and plutonium-239. Thorium is more abundant in nature than uranium. Thorium can be used as a nuclear fuel through breeding to uranium-233 (U-233). Calcium is not used as a nuclear fuel.

The most common fissile nuclear fuels are uranium-235 and plutonium-239. Thorium is more abundant in nature than uranium. Thorium can be used as a nuclear fuel through breeding to uranium-233 (U-233). Calcium is not used as a nuclear fuel.

Nuclear weapon, a device designed to release energy in an explosive manner which is result of nuclear fission, nuclear fusion or a combination of the both processes.

The principle of atomic bomb is based on nuclear fission while fusion weapons are referred as thermonuclear bombs or hydrogen bomb. Enriched uranium or plutonium is used as fissile material in atomic bomb.

Nuclear weapon, a device designed to release energy in an explosive manner which is result of nuclear fission, nuclear fusion or a combination of the both processes.

The principle of atomic bomb is based on nuclear fission while fusion weapons are referred as thermonuclear bombs or hydrogen bomb. Enriched uranium or plutonium is used as fissile material in atomic bomb.

Hydrogen bomb's enormous explosive power results from an uncontrolled, self-sustaining chain reaction in which isotopes of hydrogen (deuterium and tritium) combined under extremely high temperature and pressure to form helium in a process known as nuclear fusion.