How Does a Spinning Flywheel Defy Gravity?

TL;DR

A spinning flywheel appears weightless due to gyroscopic precession, where the torque generated by the flywheel allows it to remain horizontal when lifted. This creates a sensation of lightness, making it easier to lift the spinning wheel compared to when it is stationary.

Transcript

I am here at the University of Sydney where the mechanical engineering shop has built this incredible piece of apparatus for me. It is a forty pound, that is nineteen kilogram flywheel on the end of a meter long shaft. Can you imagine trying to hold this out horizontally with just one hand at this end? It is virtually... it is impossible, ok? No I'... Read More

Key Insights

• 🏋️ A spinning flywheel defies gravity and appears weightless due to the torque generated by its weight.
• 🏋️ Lifting a spinning flywheel feels much lighter and easier compared to lifting it when stationary.
• 🏋️ The weight of the apparatus adds to the person's weight when lifting the flywheel, but they themselves don't become lighter.
• ❓ The flywheel experiment showcases gyroscopic precession and its effects on object stability.
• 🏛️ Engineering precision and craftsmanship are required to build the apparatus for the experiment.
• ❓ The experiment demonstrates the principles of physics and the behavior of rotating objects.
• 💖 The spinning flywheel experiment can be used to spark interest and educate students about mechanics and physics.

Questions & Answers

Q: How does the weight of the flywheel create a torque that keeps it horizontal?

The weight of the flywheel generates a force that, instead of pulling it down, pushes it in a circular motion, known as gyroscopic precession.

Q: Does the spinning flywheel feel lighter to lift compared to when it's not spinning?

Yes, when the flywheel is spinning, it feels significantly lighter and easier to lift, even though its actual weight remains the same.

Q: Can the weight of the person lifting the flywheel be measured while lifting it over their head?

Yes, by standing on a scale, the person's weight increases when lifting the flywheel due to the added weight of the apparatus. However, the person themselves won't experience a decrease in their weight.

Q: What happens if the spinning flywheel is let go while being lifted overhead?

Unfortunately, the experiment does not allow for releasing the spinning flywheel, so its behavior upon release cannot be observed.

Summary & Key Takeaways

• The University of Sydney's mechanical engineering shop has built a 19kg flywheel on a meter-long shaft.

• The wheel, when spun at high speeds, creates a torque that allows it to stay horizontal and appear weightless.

• An attempt is made to lift the spinning flywheel overhead with one hand, proving the weightless effect.