— the forces acting between nucleons in atomic nuclei and determine (with electromagnetic forces) the structure and properties of nuclei. N.f. are exchange character; it is assumed that the interaction between nucleons carried by sharing pi —mezonamy; N.f. with. — short-force, their range $r_{\mathcal{я}} \sim 10^{-15}$m; they are characterized by the charge independence; N.f. depending on the relative orientation of the spins of the nucleons; N.f. inherent property of saturation: each nucleon interacts only with a limited number next to it nucleons.