Gyroscopic motion

Figure 1. A rotating gyroscope, with the angular momentum vector pointing upwards, exhibits gyroscopic motion as it resists falling over.

Gyroscopic motion describes a rotating object's tendency to keep spinning in the same direction. For example a rotating top falls over if it's not spinning but when spinning it doesn't seem to fall. A rotating object has angular momentum which must be conserved. The object will resist any change in its axis of rotation, as a change in orientation will result in a change in angular momentum.

• Gyroscopic motion is most obvious when playing with a gyroscopic top. The faster the top spins the better it resists falling over. Note the top will wobble while it spins.
• The Earth also has gyroscopic motion (and has wobbles, leading to Milankovitch cycles).
• This same physics is part of why bicycles stay upright (and why you to lean to turn a bicycle, see hyperphysics).
• Gyroscopic motion is used in inertial navigation systems with airplanes and space ships.

Gyroscopic motion can also create problems with flywheels. Additionally, gyroscopic motion can cause catastrophic failure in wind turbines. This comes from the tendency for a spinning object to want to keep spinning in the same direction.

Below is a video from Veritasium explaining the unique phenomenon of gyroscopic motion and precession. It contains an interesting demo using a spinning bicycle wheel:

You can learn more about gyroscopic motion here.

For Further Reading

• Vector
• Torque
• Milankovitch cycle
• Flywheel
• Or explore a random page