I think the complete sentence is that nuclear forces exist because the particles in the nucleus have to be bound together. These nucleic particles include protons and neutrons. Nuclear forces are also known as nucleon-nucleon interaction or residual strong force. Since, it is responsible to bind the nucleons together therefore, nuclear force is considered very important for keeping a stable structure of atom. Nuclear forces are considered very important in the nuclear physics and they were found with the discovery of the neutron by James Chadwick.
Nuclear forces
Nuclear forces
