Floating Ships

Most recent answer: 10/22/2007

Q:
I was wondering along with my mother why do cruise ships float when they are so heavey with people and food an dthings like that? Do you have this answer? Thank you in advance.
- Anonymous (age 12)
Philadelphia Pa.
A:
There are lots of heavy things on a big ship, especially the steel that the ship is made of. However, a lot of the room is taken up by something very light- air. The total density of the ship, counting all the air, is less than the density of water. (Density means the mass divided by the volume.) Anything less dense than water floats on water. If the ship sank some, it would push up water that weighed more than the part of the ship that was lowered.

Mike W.

(published on 10/22/2007)