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Name: Hannah
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Age: 11
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Date: 2000-2001

What is density and bouyancy?

Density is the amount of material packed into a certain volume. Ice cream is more dense than popcorn.

Buoyancy is an upward force on an object immersed in a fluid. The deeper you go in a fluid, the greater the pressure (force per area). That means the pressure on the bottom of the object is greater than the pressure on the top of the object since the bottom is deeper in the fluid than the top. This net, upward, difference is the buoyant force on the object. This is why a rock in water weighs less than a rock in air. Good question!

---Nathan A. Unterman

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