Mechanics > Rotational Motion > Gyroscopes DCS# 1Q50.55

PRECESSION OF EARTH'S AXIS

 

APPARATUS
globe on a gyroscope 202-10-E


DESCRIPTION
Globe with internal weight is free to pivot on the support and can be spun on its axis to show precession and nutation.

The position of the center of mass can be adjusted by screwing the weight in or out.  It has been modified so that the center of mass can be located at the point of suspension, as in Maxwell's top.  Spinning the globe so that the axis of rotation precesses about the vertical axis will cause an internal precession.  This can be made evident with a four-colored disk centered on the rotation axis.   The color at the instantaneous axis should be most prominent.  As the instantaneous axis moves through the color wheel, the color can be seen to change.  In this version, the color changes more rapidly than we would like and is hard to discern.