A ship’s hollow shape includes a large volume of air. Together, the steel and enclosed air have a lower average density than the displaced water. The upward buoyant force can therefore balance the ship’s weight.
What we found
Archimedes’ principle states that an immersed object experiences an upward force equal to the weight of displaced fluid. A solid block of steel usually sinks, but shaping steel into a wide hollow hull lets it displace much more water before becoming fully submerged. Loading too much cargo raises the average density and can reduce the safety margin. The Ridbusters then compare the wording with the original sources, look for the conditions of each observation and check whether another explanation could fit. That turns a surprising headline into a trail a young investigator can follow: claim, test, result and remaining uncertainty. A ship’s hollow shape includes a large volume of air.