Which one of the following is the energy source of stars ?

[amp_mcq option1=”Nuclear fission” option2=”Nuclear fusion” option3=”Chemical reaction” option4=”Photochemical reaction” correct=”option2″]

This question was previously asked in

UPSC CISF-AC-EXE – 2023

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The correct answer is B.

Stars generate energy primarily through nuclear fusion reactions in their core. Specifically, in stars like our Sun, hydrogen nuclei fuse to form helium nuclei, releasing a vast amount of energy according to Einstein’s mass-energy equivalence principle (E=mc²).

Nuclear fission is the process of splitting heavy atomic nuclei, used in nuclear power plants on Earth, but not the main energy source of stars. Chemical reactions involve the rearrangement of electrons and release far less energy than nuclear reactions, insufficient to power a star for its lifetime. Photochemical reactions are triggered by light, not the primary energy generation mechanism in the core of a star.

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