Key Concepts in Heat Transfer and Nuclear Reactions

conduction

process by which heat is directly transmitted through a substance when there is a difference of temperature between adjoining regions caused by atomic or molecular collisions

convection

movement caused within a gas or liquid by the tendency of hotter, and therefore less dense material, to rise and colder, denser material to sink under the influence of gravity, which consequently results in transfer of heat

fission

breaking up of heavier atomic nuclei into lighter ones

fusion

building up of heavier atomic nuclei from lighter ones

helioseismology

study of pulsations or oscillations of the Sun in order to determine the characteristics of the solar interior

hydrostatic equilibrium

balance between the weights of various layers, as in a star or Earth's atmosphere, and the pressures that support them

neutrino

fundamental particle that has no charge and a mass that is tiny relative to an electron; it rarely interacts with ordinary matter and comes in three different types

positron

particle with the same mass as an electron, but positively charged

proton-proton chain

series of thermonuclear reactions by which nuclei of hydrogen are built up into nuclei of helium

radiation

emission of energy as electromagnetic waves or photons also the transmitted energy itself