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H
ave you ever seen an insect walk on water? If you have,
you may have wondered, how can it do that? The answer
is
surface tension
. Water is made of tiny particles. The
particles are naturally attracted to one another. At the surface, where
water meets the air, the attraction between particles is very strong.
The strong attraction at the surface of the water is surface tension.
Insects like water striders can walk on water because bristles on their
feet keep them from breaking through the surface tension.
You can see how surface tension works.
Fill a glass to the top with water. Keep adding
more water a little at a time. If you are careful,
you can “overfill” the glass. The water will
form a dome above the top of the glass, but
it won’t spill out. Why? Surface tension.
Surface Tension
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