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How does the strong force hold protons and neutrons together in an atomic nucleus?

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principles of physical science Figure 1: Data in the table of the Galileo experiment. The tangent to the curve is drawn at t = 0.6.

The strong force is a fundamental interaction that acts between quarks, the subatomic constituents of protons and neutrons. While the primary role of the strong force is to bind quarks together to form these particles, the protons and neutrons within an atomic nucleus are held together by the residual effects of this force.21

This residual interaction is powerful enough to overcome the intense electrostatic repulsion between positively charged protons, which would otherwise cause the nucleus to fly apart. The force operates only at an extremely short range—approximately $10^{- 15}$ metres, which is roughly the diameter of a nucleon.3142

At the level of quarks, the strong force is mediated by massless messenger particles called gluons. Unlike the photons of electromagnetism, gluons carry a "colour" charge, allowing them to interact with one another. This unique property causes the strong force to become increasingly powerful as the distance between quarks increases, effectively locking them inside baryons like protons and neutrons.521