An eyedropper is partially filled
with water
so that it just floats in a cylinder of water. The
cylinder is
covered
with a rubber diaphragm secured with a rubber band.
Pressing on
the
diaphragm forces more water into the dropper causing it to
sink,
releasing
the pressure allows it to rise.
This illustrates the transmission
of
pressure
through liquids, Archimedes' principle, and Boyle�s Law.
NOTES
This should be prepared
using
water at
room
temperature, otherwise the dropper will sink as the water
warms up.