Final answer:
Energy balance in the sun refers to the balance between the outward pressure due to thermal gas and the inward pressure due to gravity. This balance determines the stability of the sun and the release of energy through the fusion of hydrogen. The sun's energy sustains life on Earth and drives natural processes.
Step-by-step explanation:
Energy balance in the sun refers to a balance between the outward pressure due to thermal gas and the inward pressure due to gravity. These two influences balance each other and determine the stability of the sun. The fusion of hydrogen to form helium is the source of the sun's energy, and this process releases a tremendous amount of energy through the conversion of mass to energy. The energy produced by the sun is responsible for sustaining life on Earth and driving various natural processes.