Torque-Free Precession and Wobble direction

AI Thread Summary
In the discussion on Torque-Free Precession and wobble direction, participants explore whether the wobble of a spinning plate can occur in the same or opposite direction to its spin, particularly when tossed upward or downward. The conversation references Feynman's Wobbling Plate, noting a discrepancy between observed wobble rates and theoretical predictions. It highlights that the wobble-to-spin ratio is influenced by the plate's size and shape, with concerns about how excessive amplitude affects this relationship. The distinction between torque-free precession and pure precession is also clarified, emphasizing different wobble and spin ratios. Overall, the discussion delves into the complexities of rotational dynamics and the conditions influencing wobble behavior.
Dueschnozzle
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In Torque-Free Precession of a plate, can the direction of the Wobble be either in the spin direction or retrograde to it?

For instance if you tossed the plate upward vs downward with the same spin direction. Would the wobble direction and frequency be inverse?
 
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Anyone?
 
I am not sure that understood your question correctly, but anyway you are asking about the Euler top. Try textbooks
 
wrobel said:
I am not sure that understood your question correctly, but anyway you are asking about the Euler top. Try textbooks
Hmm... I was asking more about Feynman's Wobbling Plate. Feynman said he observed the wobble at half the spin rate, but his equation says it's 2 wobbles per spin. Could both be true? From what I've read the wobble to spin ratio is determined by the size and shape, with the caveat as long as the amplitude is not too large. What happens when the amplitude is too large?
 
Dueschnozzle said:
I was asking more about Feynman's Wobbling Plate.
yes, it is a special case of the Euler top
 
wrobel said:
yes, it is a special case of the Euler top
So is this the difference between torque free precession = 2 wobble/1retrograde spin, vs roll or pure precession = 1wobble/1spin in same direction or zero spin?
 

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