Article
Article
Atomic nucleus
Article By:
Hamilton, Joseph H. Department of Physics and Astronomy, Vanderbilt University, Nashville, Tennessee.
Last reviewed:October 2019
DOI:https://doi.org/10.1036/1097-8542.060500
The positively electrically charged central core of the atom. Atoms are analogous to the solar system, with an extremely dense central core that provides the electrical positive charge to hold the negatively charged electrons in orbits through the Coulomb force, somewhat as the Sun's gravitational force holds the planets in orbit. The nucleus is composed of protons, which carry a positive electric charge, and neutrons, which have a net zero electric charge. Collectively, protons and neutrons are called nucleons. Both these particles are composed of positive and negatively charged particles called quarks, and both have a magnetic field associated with them. The masses of the protons and neutrons are 1836.2 and 1838.7 times the mass of the electron, so essentially all the mass of an atom is in its very tiny nucleus. See also: Atomic structure and spectra; Electron; Neutron; Nucleon; Proton; Quarks
The content above is only an excerpt.
About AccessScience
AccessScience provides the most accurate and trustworthy scientific information available.
Recognized as an award-winning gateway to scientific knowledge, AccessScience is an amazing online resource that contains high-quality reference material written specifically for students. Contributors include more than 10,000 highly qualified scientists and 46 Nobel Prize winners.
MORE THAN 8700 articles covering all major scientific disciplines and encompassing the McGraw-Hill Encyclopedia of Science & Technology and McGraw-Hill Yearbook of Science & Technology
115,000-PLUS definitions from the McGraw-Hill Dictionary of Scientific and Technical Terms
3000 biographies of notable scientific figures
MORE THAN 19,000 downloadable images and animations illustrating key topics
ENGAGING VIDEOS highlighting the life and work of award-winning scientists
SUGGESTIONS FOR FURTHER STUDY and additional readings to guide students to deeper understanding and research
LINKS TO CITABLE LITERATURE help students expand their knowledge using primary sources of information
