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Q: physics ( Answered,   1 Comment )
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 Subject: physics Category: Miscellaneous Asked by: johndavid7-ga List Price: \$2.00 Posted: 26 Mar 2006 10:42 PST Expires: 25 Apr 2006 11:42 PDT Question ID: 712162
 `how does metal float? such as large war ships?`
 ```Hi johndavid7, What determines whether an object will float or sink is its density, which is how heavy it is for its size. Something that is less dense than water will float on water, and something that is denser than water will sink. For example, a cork is light for its size, so it floats, while a rock is heavy for its size, so it sinks. Note that size counts, not just weight. You could have a little rock and a great big piece of cork that weighed the same amount, and the cork would still float and the rock would still sink. Metal is denser than water, and so a solid piece of metal will sink. But a ship is not solid metal--it contains a lot of air in its volume, so it is less dense than solid metal. That's how metal ships can float: they contain enough air to make their total density less than the density of water. Additional Links Here are some links to other pages that explain this same idea. Article on density by Martha Marie Day, Ed.D. on the Visionlearning site http://www.visionlearning.com/library/module_viewer.php?mid=37 Explanation by Donald Howard on Madsci Network http://www.madsci.org/posts/archives/nov2000/974385595.Ot.r.html An explanation "borrowed from Bill Nye the Science Guy" (halfway down the page) http://www.k12.hi.us/~dnekoba/billnye.htm I hope this explanation is helpful. Regards, --efn```
 `google "archimedes principle"`