Nuclear Physics Summary Notes

These vocabulary flashcards summarize key terms and definitions related to nuclear physics based on the lecture notes.

Proton

A subatomic particle with a positive charge and relative mass of 1 that defines the element.

Neutron

A subatomic particle with no charge and a relative mass of 1, which alters the isotope.

Electron

A subatomic particle with a negative charge and a relative mass of 1/1836 that affects the ion.

Nucleus

The dense central part of an atom that contains the protons and neutrons.

Radioactive substances

Materials that emit radiation from the nucleus of their atoms.

Background radiation

Radiation that is present in the environment from natural and artificial sources.

Alpha radiation

Radiation consisting of helium nuclei; has high ionizing power and limited range.

Beta radiation

Radiation consisting of electrons emitted from the nucleus; has medium ionizing power.

Gamma radiation

Electromagnetic radiation with very weak ionizing power and unlimited range in air.

Half-life

The average time it takes for the number of nuclei in a radioactive sample to halve.

Nuclear fission

The splitting of an atomic nucleus into smaller nuclei, releasing energy and neutrons.

Nuclear fusion

The process of combining two atomic nuclei to form a larger nucleus, as occurs in stars.

Fissionable substances

Materials capable of undergoing fission, such as uranium-235 and plutonium-239.

Chain reaction

A successive series of nuclear fission events resulting from the release of neutrons.

Main sequence phase

The stable phase of a star where hydrogen fusion occurs.

Supernova

A stellar explosion that distributes elements formed in stars throughout the universe.