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The CORRECT CHOICE is (d) LIGHT water reactor

Easiest explanation: The light water reactor is a TYPE of thermal-neutron reactor that uses normal water, as opposed to heavy water, as both its coolant and neutron moderator – furthermore a solid fissile element is USED as fuel. These are most common type of Thermal-neutron reactors.

Correct option is (a) Burner REACTOR

The EXPLANATION: Burner reactor is a type of reactor using U^235 as FUEL. Enriched uranium is used to increase efficiency. To prolong the FISSION reaction, fast neutrons are slowed down with a moderator and the rate of reaction is adjusted by control rods which can absorb neutrons. Some neutrons react to form plutonium, but in SMALLER amounts than the original uranium, and produces only heat as a product.

Right CHOICE is (a) True

To explain: REACTOR POWER is directly proportional to NEUTRON density, lowering the control rods will remove neutron from the reactor CORE and will decrease the power and reaction rate and raising the control rods will increase the power and rate.

Right option is (a) Nuclear fusion

For explanation: Nuclear fusion reaction TAKES place in sun as WELL as stars. The process is carried by proton-proton chain. The sun starts with protons, and through a series of steps, TURNS them into helium. Every second 600 million tons of hydrogen is converted into helium. The reaction releases TREMENDOUS amount of heat and energy.

The correct choice is (b) False

To elaborate: The ATOM as a whole is not electrically charged it is actually electrically neutral in its state. The electric charge on the proton is EQUAL in magnitude but opposite in SIGN to that of electron, the number of protons is equal to the number of electrons in the orbit.

The correct ANSWER is (c) Binding energy

Easy explanation: To disrupt a nucleus and separate in into its component nucleons, energy must be supplied from OUTSIDE and this energy is CALLED Binding energy. The NUCLEAR force acts only when the nucleons are very close to each other and binds them into compact stable structure.

Correct option is (a) Thermonuclear

Easiest explanation: To eradicate repulsive forces temperature of positively charged nuclei is raised to millions of degree resulting in plasma. The plasma should be PREVENTED from CONTACTING the walls of the container confined for a period of time of the order of a second at a minimum density. FUSION reactions are called thermonuclear because of the higher temperature requirement to trigger and sustain the reaction.

The correct option is (a) To overcome electrical repulsive forces

The EXPLANATION is: To cause fusion, it is NECESSARY to accelerate POSITIVELY charged nuclei to high kinetic energies to overcome electrical repulsive forces. This is done by rising their TEMPERATURES to hundreds of millions of degree RESULTING in plasma.

The correct choice is (c) Multiplication factors

The EXPLANATION: The net neutrons produced per initial neutron accounting for all possible LOSSES is called multiplication factor (K). If: K < 1 = system is subcritical.

K = 1 = System is CRITICAL.

K > 1 = system is super critical.

Correct answer is (c) Candu reactor

To ELABORATE: Heavy WATER composed of heavy hydrogen isotope H-2 is USED as a moderator and coolant in some POWER and research reactors. These reactors use heavy water as a moderator and primary coolant and light water as SECONDARY coolant.

Right option is (b) Hydrogen

The explanation: Most of the mass of the atom is in nucleus. The RED dot is a proton it has positive CHARGE of 1 unit, and black ONE is an electron, which has a NEGATIVE charge of -1. There is only one orbital for hydrogen.

Right ANSWER is (b) Causes no pollution

Easy explanation: Most ATTRACTIVE part of nuclear energy is that it has no combustion products and under SAFE working conditions contributes no pollutant to air. SITE selection is COMPLETELY independent of geographical area.

Right answer is (a) Fast REACTOR

To elaborate: A fast reactor is a category of nuclear reactor in which the FISSION chain REACTION is sustained by fast neutrons, as opposed to thermal neutrons USED in thermal neutron reactors. The fission process is caused by fast neutrons and the reactor has no MODERATOR and the core size less.

Right option is (a) Breeder reactor

Explanation: A breeder reactor is a NUCLEAR reactor that GENERATES more fissile MATERIAL than it consumes. In this reactor fertile material is converted into initial fissile material. For e.g. natural uranium is the FUEL, THORIUM is converted into U^233.

Correct option is (c) It shouldn’t be chemically unstable

Easiest explanation: It should be chemically stable and should not e decomposed DUE to NUCLEAR radiation. It should not absorb neutrons but SLOW down the neutrons as early as possible. It should have HIGH resistance to corrosion as it has to work under high pressure and TEMPERATURE.

Correct ANSWER is (a) NUCLEAR fusion

Easiest explanation: Nuclear fusion is the process which involves fusion of two light nuclei of low mass to PRODUCE a heavy nucleus which results in decrease of mass and RELEASE of enormous amount of energy. All ATOMIC bombs prefer nuclear fission process.

The correct answer is (c) Otto Hahn

The best I can EXPLAIN: Nuclear fission of heavy metals was discovered by German Otto Hahn on DECEMBER 17, 1938 and was explained theoretically by Lise Meitner and her nephew Otto Robert Frisch on 1939. Frisch NAMED Frisch names the PROCESS by analogy with biological fission of LIVING cells.

Correct option is (c) Molecular bond

The explanation is: A covalent bond is also called as molecular bond, which involves sharing of ELECTRON pairs between atoms. These electron pairs are KNOWN as SHARED pairs or BONDING pairs, when these share an electron than it is called as covalent bonding.

Correct answer is (a) Fast BREEDER reactor

Easy explanation: If the reactor produces more fissionable material than it consumes, it is fast breeder reactor. The breeder fuel consists of both FERTILE and fissile material. The number of NEUTRONS RELEASED is sufficient to PROPAGATE the fission reaction and to produce more fissionable material by conversion of fertile isotopes to fissile isotopes.

The correct choice is (B) Helium

The EXPLANATION is: The masses of three atomic sub-particles are,

NEUTRON mass, MN = 1.008665 amu

Proton mass, mp = 1.007277 amu

Electron mass, me = 0.0005486 amu.