Learn more physics!
Why do cargo ships float?
- Teri Navarro (age 13)
Corinth, Ms, Alcorn
Teri- Things float as long as the water they displace (move out of the
way) weighs as much as they do. Whether that happens depends on the
density of the thing. The density of an object is equal to its weight
divided by its volume. Every substance, including water, has its own
density at a given temperature (density can vary as a substance gets
hotter or colder). Any substance that is less dense than water floats
while one that is more dense sinks. However, even though cargo ships
hold a ton of heavy cargo, they have chambers of air inside that make
them mostly hollow. This brings me to the main point... an object that
is hollow like a cargo ship floats if its density-its weight divided by
its total volume is less than the density of water. Thanks for your
(republished on 07/31/06)
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