Final answer:
If the Earth had the density of a nucleus, its radius would be only about 200 meters compared to the actual radius of approximately 6.4 x 10^6 meters.
Step-by-step explanation:
Protons and neutrons, collectively called nucleons, are packed together tightly in a nucleus. With a radius of about 10-15 meters, a nucleus is quite small compared to the radius of the entire atom, which is about 10-10 meters. Nuclei are extremely dense compared to bulk matter, averaging 1.8 × 1014 grams per cubic centimeter. If the earth's density were equal to the average nuclear density, the earth's radius would be only about 200 meters (earth's actual radius is approximately 6.4 x 106 meters, 30,000 times larger).