What holds an electron revolving around the nucleus? Why don't they just go zooming around everywhere?
What causes the force that holds atoms together? The answer is electricity and magnetism. The atom's center, or nucleus, is positively charged and the electrons that whirl around this nucleus are negatively charged, so they attract each other. The reason the force is strong is because the atom is so small. The distance between the nucleus and the electrons is about 1 Angstrom (named after a famous scientist); this is 0.00000001 cm (10-8 cm) or about 4 billionths of an inch. Since the electric force varies with the distance between the positive and negative charges like 1 over the distance squared, the force gets large for small distances.
Mac Mestayer, Staff Scientist (Other answers by Mac Mestayer)