Understanding gyro without angular mom

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Discussion Overview

The discussion centers on understanding the motion of a gyroscope, specifically precession, without relying on the concepts of angular momentum or torque. Participants explore alternative explanations using Newton's laws and intuitive reasoning.

Discussion Character

  • Exploratory, Conceptual clarification, Debate/contested

Main Points Raised

  • One participant expresses a desire to understand gyroscopic motion intuitively through Newton's laws, emphasizing a need for a non-angular momentum perspective.
  • Another participant suggests that angular momentum is essential for understanding the phenomenon, indicating a disagreement on the necessity of this concept.
  • A different participant shares an anecdote about learning gyroscopic motion through a ping pong ball analogy, suggesting that visualizing forces can aid in comprehension.
  • One participant proposes that considering the flywheel as a composite object with particles moving in various directions may help explain precession without invoking angular momentum.

Areas of Agreement / Disagreement

Participants do not reach a consensus; some argue for the necessity of angular momentum in understanding gyroscopes, while others seek alternative explanations that do not rely on it.

Contextual Notes

Participants express varying levels of understanding and comfort with the concepts of torque and angular momentum, indicating that the discussion may depend on individual interpretations and definitions of these terms.

h0dgey84bc
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Hi,

I understand the motion of a gyroscope through considerations of torque and angular momentum, I have no issue with deriving it and imagining it by considering these things, but I somehow feel I still don't understand precession on an intuitive level. I was wondering if anyone could help me understand the motion of a gyroscope without invoking angular momentum/torque, just by soley considering Newton's laws.

Just to avoid confusion, take the z axis as out of the screen, y-axis from bottom to top, x-axis from left to right and I'm considering a flywheel rotating along an axis in the x-direction. Its axial rod is sat on a pivot to the left, gravity is in the negative z direction. Hence torque is in the y-direction, and precession occurs about the z axis.
I've attempted a drawing, that I've attached.

Like I say, I'm happy with the ang mom/torque explanation, I am just looking for a Newtonian one.

Thanks
 

Attachments

  • precession.jpg
    precession.jpg
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Don't be afraid of angular momentum. You really need it here.
Even Newton used it.
 
clem said:
Don't be afraid of angular momentum. You really need it here.
Even Newton used it.

I'm not afraid of angular momentum, I fully understand the explanation of precession via angular momentum and torque, and no issues with it at all. However I have an itching to understand this via simple forces as well, ultimatley such a picture must be possible here. I think that thinking of the flywheel as a composite object, made up of smaller particles, some of which are moving up, some down, some left some right, etc, when the flywheel spins, is key to understanding why the flywheel precesses when spun, but falls otherwise. Can't quite fully picture it just yet though.
 
I never understood gyroscopes (I still dont) until I read the ping pong ball on a string explanation. as the ball circles around each time it strikes a paddle and glances off at a very slight angle. the result is a downward force on the paddle. you can then easily imagine the effect on the ping pong balls rotation.
 

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