Final answer:
The Sun produces energy through nuclear fusion, where four hydrogen nuclei fuse into one helium nucleus with a mass slightly less than the original hydrogen nuclei, converting the lost mass into energy.
Step-by-step explanation:
The Sun produces energy through a process known as nuclear fusion. In the Sun's core, four hydrogen nuclei (1H) undergo a series of reactions to fuse and form a single helium nucleus (4He), along with the release of two positrons and energy. This energy generation occurs due to the fact that the helium nucleus has slightly less mass than the total mass of the four hydrogen nuclei. According to the mass-energy equivalence principle (E=mc²), this loss of mass is converted into a tremendous amount of energy, which radiates outward from the Sun's core.
The steps leading to the creation of helium involve a more complex series of events, known as the proton-proton cycle, which results in a net reaction where around 0.7% of the mass of the original hydrogen nuclei is converted into energy. This conversion of mass into energy produces approximately 3.6 × 10¹¹ kJ of energy per mole of helium produced, which is significantly greater than the energy yield from nuclear fission or chemical combustion. Consequently, the Sun's energy travels from its core to its surface through several heat transfer methods, including radiation, conduction, and convection, before it is emitted as heat and light.