Strong Nuclear Force
The powerful fundamental interaction that binds quarks together into hadrons and holds protons and neutrons together inside the atomic nucleus.
Governing formula
F_strong ≫ F_EM (Range r ≤ 1–3 fm)
SI unit
N (Newtons)
In depth
Mediated by massless gluons carrying color charge (quantum chromodynamics). At sub-femtometer scales, it is the strongest of the four fundamental interactions (~100 times stronger than electromagnetism), but drops rapidly to zero beyond ~3 femtometers.
Examples in the real world
Overcoming the intense electrostatic repulsion between closely packed positively charged protons to keep atomic nuclei intact.