Final answer:
Neutrons in an atomic nucleus interact via the strong nuclear force, a powerful attractive force that acts at very short ranges and offsets electromagnetic repulsion among protons, ensuring the nucleus remains intact.
Step-by-step explanation:
The interaction between two neutrons involves the strong nuclear force, which is a very strong attractive force acting over very short distances within the atomic nucleus. It is responsible for binding protons and neutrons together in atomic nuclei, effectively countering the electromagnetic repulsion that would otherwise push apart the positively charged protons. The strong force is capable of overcoming the electromagnetic force, which can manifest as either attraction or repulsion, depending on the charges involved. The strong nuclear force does not influence the electrons in an atom since it only acts on the particles within the nucleus, namely protons and neutrons.