A large amount of energy is produced in the center of sun by which phenomenon?

• A. Nuclear fission
• B. Nuclear fusion
• C. Radioactive decay
• D. Chemical reaction

Answer: (B)

Stars generate energy primarily through nuclear fusion. In the Sun’s core, extreme temperatures and pressures force hydrogen nuclei to collide and fuse into helium. This process releases a large amount of energy because some of the mass involved is converted into energy (mass-energy equivalence), and fusion yields far more energy per reaction than chemical reactions. The intense conditions specifically favor hydrogen fusing into helium, as seen in the proton-proton chain (and the CNO cycle in heavier stars), rather than splitting heavy nuclei or relying on radioactive decay. Nuclear fission breaks apart heavy nuclei and is not what powers the Sun, and chemical reactions involve only electrons and release orders of magnitude less energy. So the Sun’s warmth and light come from hydrogen fusion into helium in its core.