Figure 1. The electrical force pushing protons apart and the strong force acting on both protons and neutrons inside a nucleus.[1]

Nucleon is the collective term for protons and neutrons. Nucleons are the particles found in the nucleus of atoms. Most notably nucleons are a result of the strong force holding the atoms together—which is stronger than the electric force pushing them apart (see figure 1). Through a beta decay, the weak force can turn one nucleon into another nucleon—either protons to neutrons or neutrons to protons. Nucleons are incredibly small, about 10-15 m, 10,000x smaller than an atom! Please see size of the universe for some online demonstrations to show this scale.

Electrons are not nucleons, therefore, don't feel the strong force. The strong force only acts on objects made of quarks.

To learn more about protons please see 'What's a proton' by Prof. Matt Strassler or hyperphysics.

To learn more about neutrons please see hyperphysics.

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