What happens to the nuclear force when nucleons are separated by more than a few femtometres?
**Nuclear force** strong, short-range ~1 fm, attractive, charge independent, saturated in large nuclei because each nucleon interacts only with neighbors, not all others, so BE/A saturates ~8 MeV, primary factor limiting stable nuclei size is Coulomb repulsion between protons growing as Z² vs strong force saturating, beyond Z≈83 no stable nuclei, competition between Coulomb and strong. The nuclear force is short-ranged and drops rapidly to zero beyond a few femtometres, leaving only weaker forces like Coulomb repulsion or gravity to act between nucleons. Using E_n = -13.6/n² eV, r_n = n² a₀, L
Ref: NCERT > Physics Book > Atoms and Nuclei > Radioactive Decay, Nuclear Forces and Stability