Final answer:
The nucleus of an atom doesn't fly apart because there is a strong nuclear force that holds it together, which overcomes the electromagnetic repulsion between protons.
Step-by-step explanation:
The protons in the nucleus of an atom do repel each other due to electromagnetic forces. However, the nucleus doesn't fly apart because there is another force called the strong nuclear force that holds the nucleus together. The strong nuclear force is much stronger than the electromagnetic force, so it overcomes the repulsion between the protons.
The strong nuclear force is responsible for binding the protons and neutrons in the nucleus. It is a short-range force that only acts within the nucleus, while the electromagnetic force acts over longer distances. This means that the strong nuclear force can overcome the repulsion between protons in a small area, keeping the nucleus stable.
So, it is the balance between the repulsion of protons due to the electromagnetic force and the attraction of protons and neutrons due to the strong nuclear force that allows the nucleus of an atom to stay together and not fly apart.
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