Gyroscopic Precession
Relate a spinning rotor’s angular momentum to gravitational torque and slow precession around a vertical axis.
Free theory articleRelate a spinning rotor’s angular momentum to gravitational torque and slow precession around a vertical axis.
Concept & interpretation
A rapidly spinning rotor under gravitational torque can steadily turn about the vertical. This module uses the slow-precession approximation, rather than a full solution of rigid-body dynamics.
Experiment: tilt versus spin
Open the Gyroscopic Precession module and enter the worked example using its labelled controls.
- Change Tilt from vertical theta from90 to30. Torque halves to0.5 N·m while Ω stays0.5 rad/s. The horizontal component L sin θ also halves, so the same precession rate suffices.
- Set Spin angular speed omega to200. L doubles to4 kg·m2/s, Ω halves to0.25 rad/s and the period doubles to8π≈25.1327412287 s.
- Inspect the vertical axis, tilted L axis, angle and projected precession cone. Drag to pan and use Reset view to recover the original framing.