LOCKED : Study Notes on Gyroscopic Precession

Demonstration of Gyroscopic Precession with a Flywheel

Introduction to the Experiment

• Location: University of Sydney

• Equipment: 40 pound (19 kg) flywheel on a 1-meter long shaft

• Initial Challenge: Attempting to hold the flywheel horizontally from one end is nearly impossible due to its weight.

Background on Weight and Torque

• Description of the Flywheel:

  • Weighs 40 pounds (19 kg)

  • Long shaft (1 meter)

• Common Experience: Holding heavy objects horizontally is difficult, showcasing the challenge posed by gravity.

Initial Challenge Attempt

• Demonstration of Holding the Flywheel:

  • Request made for a participant to hold the flywheel horizontally.

  • The difficulty in doing so highlights the significant weight and resistance.

Introduction to the Main Experiment

• Preparation:

  • Discussion on spinning the flywheel to exploit gyroscopic effects.

  • Spin the flywheel up to several thousand RPM before the next demonstration.

Outcomes of Spinning the Flywheel

• Release of Left Hand:

  • Upon releasing one hand while the flywheel spins, the shaft remains horizontal.

  • Observation: The flywheel appears to be weightless due to gyroscopic precession.

  • Concept of Gyroscopic Precession:

    • Defined as the phenomenon where the weight of a spinning object causes a torque that pushes it around in a circle instead of allowing it to fall down.

Secondary Challenge: Lifting the Spinning Flywheel

• Attempt to Lift the Flywheel Overhead

  • Suggestion made to test lifting the flywheel to understand the effort involved when spinning versus at rest.

  • Initial trial to lift the non-spinning flywheel revealed significant difficulty, warranting caution due to its weight.

Insights on Lifting a Spinning Flywheel

• Observations During Attempt:

  • The challenge to lift it overhead while spinning invoked anticipation and caution.

  • The spinning flywheel felt substantially easier to lift, despite being 40 pounds (19 kg).

• Participant Experience:

  • Remarked that the flywheel seemed to want to ascend on its own during the lift, in stark contrast to lifting it when stationary.

Reflection on Weight Perception

• Discussion About Weightiness:

  • Without spinning: Feeling heavy and awkward.

  • With spinning: Feels light, almost effortless.

  • Important Note: It is not actually weightless; the perception of lightness is due to the dynamics of gyroscopic effects.

Scale Measurement Exercise

• Measure Body Weight:

  • Initial weight (without flywheel): approximately 72 kg (159 lbs).

  • Weight with flywheel lifting: approximately 91 kg (200 lbs).

• Relationship Between Weight and Lift:

  • Prediction discussed regarding the scale reading during the lift of the spinning flywheel.

  • Scale Prediction Inquiry:

    • Query posed: Will the reading be more, less, or equal to 91 kg while lifting the spinning flywheel?

Conclusion and Prediction

• Invitation for Participation:

  • Viewers encouraged to make their prediction regarding the scale reading.

• Final setup included a countdown to the lift, building suspense for the outcome of the experiment.