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Foucault Pendulum Google Doodle for September 18th
Foucault Pendulum doodle for today is an animation that shows the current
time according to pegs that have been knocked down by a swinging pendulum,
in commemoration of
Jean Bernard Léon Foucault's birthday on September 18, 1819. It
is very cool. After watching its motion over a period of many minutes,
the update appears to occur only when the web page is refreshed, rather
than with real-time action. I also noticed what looks like an error
in the displayed position of the pendulum on the near side of the peg
array that is illustrated in the screen capture below. Unless the pendulum
has just been released, it is impossible for the path to lie between
two standing pegs.
The pendulum bob's path should never pass between two standing
pegs unless it had just been initially released.
Probably most widely seen Foucault Pendulum is (or was) at the Smithsonian
National Museum of American History, in Washington, D.C. I remember
seeing it during a class field trip when I was in the 6th grade (Annapolis,
Maryland). When Melanie and I took our kids to see the museums back
in the 1990s, the most of the building was closed to the public due
to renovation, so we didn't get to see it. As it turns out, the pendulum
was removed from display in 1998. Bummer. There are, however, many other
locations in the U.S. and around the world where very nice Foucault
Pendulums are in operation. It is mesmerizing to stand and watch a big
one in action. Even the little-known Besser Museum in Alpena, Michigan,
has its own Foucault Pendulum.
remember many moons ago in the late 1970s when I was working as an electrician
prior to entering the USAF, I made a service call to St. John's
College in Annapolis, Maryland. There, in a pit in the basement of the
Observatory building, was a functional
Foucault Pendulum. Its cable was attached to a point at the ceiling
of the building's fourth story. At the time it had only been less than
a decade since seeing the one at the Smithsonian, and seeing it really
made my day. A restoration project was begun by the Class of 2011 (see
Facebook page and a
Oh, if my memory serves me correctly, the service
call had to do with an outdoor lighting circuit that kept blowing a
fuse. It was an 18th century building with knob and tubing wiring in
many parts of it, and circuit breakers had not been installed yet. The
problem was caused by a short inside a section of buried galvanized
conduit. Navigating through a nasty section of crawl space that was
filled with nasty cricket spiders, slugs, cockroaches, and every other
Jones and the Temple of Doom critter had a lot to do with my
decision to make a trip to the Air Force recruitment office.
Click on the clock icon to display slider controls
for time and time zone.