Foucault's Pendulum and Inertial Oscillation

Photographing the locus of a pendulum

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Pendulum
Weight: a penlight hung facing up
Length: 90cm

The pendulum was hung above the center of a rotating table.

Photography
The laboratory was made dark, and using long exposure, the locus of the pendulum was photographed with a camera set on the rotating table.
 
Experimental Process
The penlight was turned on, and swung in a straight line from the point of view of outside the rotating system.