Couldn't find element LayerAd

Error finding content

The Nuclear Force - Windows to the Universe

Shop Windows to the Universe

Science, Evolution, and Creationism, by the National Academies, focuses on teaching evolution in today's classrooms. Check out the other publications in our online store.
The strong force keeps also the protons together in the nucleus, despite their mutual electrostatic repulsion.
Contemporary Physics Education Project

The Nuclear Force

The protons in the nucleus of an atom are positively charged. If protons interact, they are usually repelled (pushed apart) by the electromagnetic force. However, when two or more nuclei come very close together (on the order of 1 femto-meter (fm) =10-15 meters), their interaction becomes dominated by another force, the nuclear force, whose intensity is much higher (about 100 times) than the electromagnetic (repulsive) force.

The nuclear force is also known as the strong force or the color force. This is one of the four fundamental forces that govern all the interactions in the Universe.

The nuclear force keeps together the most fundamental of elementary particles known, the quarks, which combine to form the protons and neutrons in the atomic nucleus. The nuclear force also keeps the protons together in the nucleus, despite their mutual electrostatic repulsion. Beyond the distance of 1 fm the nuclear force decreases sharply, becoming practically negligible.


Shop Windows to the Universe Science Store!

Cool It! is the new card game from the Union of Concerned Scientists that teaches kids about the choices we have when it comes to climate change—and how policy and technology decisions made today will matter. Cool It! is available in our online store.

Windows to the Universe Community

News

Opportunities

You might also be interested in:

Atomic Nucleus

Atoms are composed of a massive, central nucleus surrounded by a swarm of fast-moving electrons. The nucleus is made up of protons and, in most cases, neutrons. Almost all of the mass (more than 99%) of...more

Neutron

A neutron is a sub-atomic (meaning it is smaller than an atom) particle. The nucleus of an atom is made up of neutrons and protons. Neutrons and protons are almost exactly the same size (a neutron has...more

The Neutron Capture Process

Neutron capture can occur when a neutron approaches a nucleus close enough for nuclear forces to be effective. The neutron is captured and forms a heavier isotope of the capturing element. When the new...more

Fusion Reactions

Nuclear fusion is a process where two or more nuclei combine to form an element with a higher atomic number (more protons in the nucleus). Fusion is the reverse process of nuclear fission. Fusion of light...more

The Nuclear Force

The protons in the nucleus of an atom are positively charged. If protons interact, they are usually repelled (pushed apart) by the electromagnetic force. However, when two or more nuclei come very close...more

IMF

IMF stands for Interplanetary Magnetic Field. It is another name for the Sun's magnetic field. The Sun's magnetic field is enormous and is carried by the solar wind. The solar wind and magnetic field are...more

The Hydrogen Fusion Process

The basic Hydrogen fusion cycle involves four Hydrogen nuclei (protons) and two electrons and yields a Helium nucleus, two neutrinos and six photons. This process occurs in three steps: the first one is...more

Fusion Inside the Stars

Fusion in the core of the stars is achieved when the density and temperature arising from the gravitational pressure are high enough. There are different fusion cycles that occur in different phases of...more

Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part by the National Science Foundation and NASA, our Founding Partners (the American Geophysical Union and American Geosciences Institute) as well as through Institutional, Contributing, and Affiliate Partners, individual memberships and generous donors. Thank you for your support! NASA AGU AGI NSF