I got this wrong on a test can you help?

Question

The nucleus contains protons and neutrons. Being positively charged, the protons repel each other. The nucleus should fly apart due to the repulsive force. Yet, the nuclei of most atoms are stable – explain.

Answer 1

What do you mean? Protons do not repel each other do they? Nuclei of atoms are mostly stable do to the nature of electron balancing between different molecules and atoms.

Answer 2

There are two nuclear forces that act on particles in atoms.

The first is the "weak force". This is what attract electrons to protons and repels protons from protons and electrons from electrons. This force is the primary force when the separation of particles is great. But when you look inside the nucleus you notice that all the protons are tighty packed. This leads us to the second force.

The second force is the "strong force". This is what maintains the protons in the nucleus tightly packed. This force attracts the protons to eachother when the separation distance is small. It is much stronger that the weak repulsive force they experience due to the "weak force" and therefore keeps the nucleus together.

This is just an analytical explanantion but it should satisfy most highschool physics problems. If you want to know more about the details look up the elementary particles of protons. Googling Quarks and Gluons or Strong Force should give you some good descriptions.