Tuesday, August 25, 2009

365 Theme 189: Moving

"And yet it moves!"

Two views of the Foucault pendulum at the Franklin Institute. The pendulum shows that the earth rotates on its axis. As the pendulum swings back and forth the plane it swings in rotates with the earth. For this pendulum the motion is shown by having the bob knock over pins arranged in a circle (click on the top photo to see the pins, some of which have been knocked over).

The phrase, "and yet it moves" is often attributed to Galileo, with him supposedly saying it after being forced to recant his support for the heliocentric view of the solar system (which we now know is correct). It is unlikely that Galileo actually said this a the trial, although he most certainly believed it.

1 comment:

Chesney said...

Very cool, love this series of pics so far! Can hardly wait to see what you come up with next!