Question

Atomic reactor is based on
A. controlled chain reaction
B. uncontrolled chain reaction
C. nuclear fission
D. nuclear fusion

Answer 1

Hint: Atomic reactors are also known as nuclear reactors. They are a device used to carry out a nuclear reaction. Any nuclear reaction involves reactions between the nuclei of two radioactive isotopes. The atomic reactor works on the splitting of the nucleus of a radioactive element.

Complete answer:
An atomic reactor, also known as a nuclear reactor, is a device used in generating high amounts of nuclear power. They are used for producing radioactive nuclides, or radioactive isotopes.
The principle reaction happening in the atomic reactor is the principle basis for running an atomic reactor. The principle involved in the nuclear reactors is the splitting of one radioactive nucleus into small components. After this a chain reaction happens that creates this splitting of nuclei repeatedly.
Since, the splitting of one radioactive nuclide into two is called as nuclear fission, therefore, nuclear fission is the basis of the atomic reactor.
The fragments or particles of the nuclide are in a very excited state, and hence emit subatomic particles, that consist of neutrons, photons, etc. Then these emitted species are again subjected to fission.
Hence, an atomic reactor is based on nuclear fission.

So, option C is correct.

Note:
Chain reactions are a basis for nuclear weapons and atomic bombs. Since these chain reactions result in a continuous emitting of radioactive species, hence they produce a lot of heat and energy, which makes them useful for weapons and bombs.