If you leave your ship set up like this for a long
while, the water might evaporate and air bubbl
es
might appear in the tube. If that happens, you’l
l
need to push the plunger very carefully inward,
otherwise the tube may burst. Make sure to
change the water from time to time, or conduct
some air-based experiments!
?
WHAT’S
HAPPENING
Your entire ship will rise and fall, as
though it were sailing over a series of
waves. If you push one plunger inward,
the water will pass through the tube into
the other syringe, pushing its plunger the
same distance outward. The plunger
presses against the tabletop and lifts
the entire ship upward.
4
Insert the cabin into the base panel, and
position the tube firmly between the syringe
and the top of the cabin so that it can’t move.
Make sure that there are no kinks in the
tube. Slowly push the plunger of the full
syringe inward.
4
WHAT ARE HYDRAULICS?
The word hydraulics comes from Greek and
means water (“hydro”) and pipe (“aulos“). In
science, hydraulics is the study of the flow
behavior of liquids. That sounds pretty
complicated, but you’ve actually already
explored what it means using your model, i.e.
how a liquid is used to transfer a force. The
pressure that is exerted on a pump
is transmitted to the water, and the water then
passes this pressure to a piston, which
performs some kind of work. This is a
hydraulic transmission system.
WHERE ARE
HYDRAULICS USED?
Today, hydraulics are used for transferring
forces in very big machines. F
or example, they
are used in agriculture and construction f
or
forklifts, cranes, and diggers. Hav
e you ever
noticed the tubes on your bik
e that run from
the handlebars right to the brakes? E
ven
there, you’re using a hydraulic system with
brake fluid. Instead of water, special oil is
often used as it doesn’t evaporate when it
gets warm, or freeze when it gets c
old.
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