An introduction to nuclear physicsPart-2 explores the two-nucleon potential through the study of the deuteron problem, nucleon-nucleon scattering, and also presents a meson theoretical description of the nuclear potential. Part-3 deals with the nuclear structure through different models, e.g., liquid-drop model, Fermi gas model, nuclear shell model, collective model. Part-4 develops different theoretical models for nuclear reactions, e.g., compound nucleus, statistical model, continuum model, optical model, direct reaction mechanism. Part-5 covers different aspects of nuclear excitations and decays through -, -, -decay, and photo-disintegration of the n-p system.