School of Physics Lecture Demonstration Manual

Mi-7 Double Wheel Gyroscope

Published: Thursday 09 March 2006 - Updated: Thursday 24 March 2011


To demonstrate that the angular momentum is a vector quantity.



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Double Wheel Gyro Diagram


Double Wheel Gyroscope


Two bicycle wheels are mounted on a single arm and may be spun to high speed independently. If one wheel is spun the normal precession demonstration may be carried out. If the second wheel is spun so that it is rotating in the same direction as the first, the precession rate is increased. If instead, the second wheel is made to rotate in the opposite direction to the first, the angular momentum vectors cancel and the system has essentially no angular momentum and the wheels act as dead weights.

Safety notes

Electrical Safety 


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