With the big Pendulum of Foucault in the entrance of the Huygens building the rotation of the earth is demonstrated. It looks as if the axis of swing of the pendulum would make a full turn in a bit more than 30 hours and 30 minutes (due to the northern latitude of Nijmegen). In reality it is the earth which rotates "under the pendulum", while the pendulum itself conserves its orientation with respect to the universe, thanks to its momentum.
Listen to the explanation on the mechanism in the video of Professor Jim LaBelle (Darmouth; engelstalig). Find further explanations on the
principle according to which the pendulum works, or
mathematical and physical descriptions of the phenomenon and background information on the pendulum on
Wikipedia.)
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The pendulum of Foucault in the Huygens building Short video of the launching of the Foucault pendulum by queen Beatrix:
mov (2330KB) or gif (1995KB) |