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What happens when water falls through air? Water forms drops.
Drops are small
volumes
of water with surface all around. The
skinlike surface tension pulls all around the outside of the drop. The
pulling results in a sphere. Next time you are in the shower, look
closely at the falling water. What do you see?
Without surface tension,
rain
falling from
clouds
might fall
in sheets or strings. Without surface tension, water landing on
a window, a car, or a leaf would
spread out into a thin film. But
the water doesn’t make a thin film.
It forms dome-shaped bits of water
called beads. Why do you think
water forms beads when it falls
on a waterproof surface?
Remember surface tension the
next time you watch water striders
zip across the water. The little
insects glide over water as if they
were skating on ice because of
surface tension.
Water forms beads.
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