Internal thermal energy of a thermodynamic system is a function of the energy inside, minus the kinetic energy of movement of the entire system and the potential energy of the total system because of the external force fields. It pays attention to the system’s energy gains and losses due to internal changes Internal thermal energy is calculated in difference from a standard state reference zero. The difference is calculated by thermodynamic processes that transport the device to the current state of interest.
1. Internal Thermal Energy: Nuclear Fusion
In general, energy is emitted from a fusion process that creates nuclei lighter than iron-56 or nickel-62. These elements have very little weight per nucleon and strong energy binding per nucleon. The fusion of nuclei that is lighter than those emit energy (exothermic process) while the fusion of heavier nuclei induces energy retained by product nucleons, which results in an endothermic reaction. Conversely, nuclear fission is the reverse process. The lightest elements, such as hydrogen and helium, are typically more fusible and more fissionable, whereas the heavier elements, such as uranium , thorium and plutonium.
Nuclear fusion is a process in which one or more separate atomic nuclei and subatomic particles (neutrons or protons) have been fused. The mass difference between reactants and products is either the energy release or the energy absorption. This mass difference comes from the difference between the nuclear “binding force” before and after reaction. Fusion is a mechanism that activates active stars or stars of “main sequence” or other major stars.
2. Energy Source: Gravitational Contraction
Gravitation contraction is the process that Kelvin and Helmholtz first suggested to describe the Sun’s energy source in the late 19th century.
Scientists and philosophers of antiquity have since attempted to understand the physical process that causes the Sun to shine. As the correct answer, nuclear reactions were unknown, Sun’ s gravitational potential by constant contraction or by “gravitational contraction” was the primary candidate for a source of solar energy.
Energy source is the gravitational collapse of the star formation-this crash would provide enough energy to heat the protostar gas to around 15 million Kelvins at the ignition core of hydrogen fusion. The knowledge of the gas cloud mass and the distribution allows for a reasonably comprehensive simulation, as the viral theorem shows that half of the energy from the gravitational crash is in cinematic energy.