Ocean waves off the coast of Mexico
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copyright 2002 University Corporation for Atmospheric Research
What is a Fluid?
When you hear the word Fluid
you might think of a liquid like water or juice - something that you can stir up with a spoon. That's right
- all liquids are
fluids. But did you know that gases like air are fluids too?
If you can stir something up with
a spoon or blow it through a straw, it's a fluid. Actually, all liquids
and gases are fluids. In space and inside stars there's
another kind of fluid called a plasma. Plasma makes up stars.
Most of the universe is made of fluid! All of these things are fluids: oatmeal, jello, milk, blood, rain, the Earth's
giant gas planets like Jupiter,
stars like the Sun, and
huge clouds of
gas and dust in space. Can you think of others?
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