Nuclear Fusion reactions power the Sun and other stars. In a fusion reaction, two light nuclei merge to form a single heavier nucleus.The process releases energy because the total mass of the resulting single nucleus is less than the mass of the two original nuclei
Explanation:
Nuclear fusion is a process in which atomic nuclei are fused together to form heavier nuclei. ... Like fission, nuclear fusion can also transmute one element into another. For example, hydrogen nuclei fuse in stars to form the element helium.