Problem description:

It is now known that when the distance between nucleons is less than 10- 15 meters, a strong force will suddenly appear. Excuse me, there is no Coulomb repulsion between the nucleons in the nucleus, such as neutrons and neutrons, so are they close together? If not, what force made them overcome this powerful force, and there was a distance between them?

Analysis:

What makes the nucleus close together is called strong force (also called strong nuclear force), and nothing can be said. There is still weak force (also called weak nuclear force) in the nucleus without distance, so that there is no distance between neutrons and protons at all. We all know that the effective range of strong nuclear force is very small, but the effective range of weak nuclear force is also very small, but it is a little bigger than strong nuclear force, so if the nucleus is too big, the weak nuclear force will exceed the strong nuclear force, so most of the larger nuclei are easy to fission and decay.