Why do ships float but stones sink?
Show answer & explanation
Answer: Ships displace more water
Water pressure lifts ships up — Wrong. Water pressure acts equally in all directions. Ships float because of buoyancy - they displace a volume of water weighing more than the ship itself.
Ships displace more water ✓ — Correct! This is Archimedes' principle! A ship's hollow shape lets it displace a huge volume of water. If the water displaced weighs more than the ship, it floats. A stone is solid and compact - it can't displace enough water to equal its weight, so it sinks. That's why a steel ship floats but a steel ball sinks!
Engines keep ships afloat — Wrong. Engines power the ship but don't make it float. Even without engines, a properly shaped hull floats by displacing water equal to its weight.