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Author Topic: Mechanics of the throw flip  (Read 2465 times)

ortwin

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Re: Mechanics of the throw flip
« Reply #30 on: July 05, 2022, 04:35:26 PM »

I wasn't really surprised, except for how well it fit the theory of the relation between the height of the wrap and the center of mass of the top.
...
So we think that we could soon get comfortable with why and how  a top flips with a sideways throw?
But what about the "downward" throw as can be seen for example in videos of Gus:



It would be interesting to see a slow motion video of that type of throw. In which plane is the axis of the top rotating and why?
ta0 do you accept this homework?



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Texture

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Re: Mechanics of the throw flip
« Reply #31 on: July 05, 2022, 05:09:18 PM »

I know traditionally the overhead or downward throw was done with a string length long enough so the top wouldn’t actually turn over, but now most people use a shorter string and hold the top the same way as in the side throw. I personally use a length more in the middle, so the the top does only a half rotation.
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ta0

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Re: Mechanics of the throw flip
« Reply #32 on: July 05, 2022, 07:00:39 PM »

I think you sum it up nicely in these three sentences. But there is no correct angle, if I remember correctly the angle is irrelevant.
You are right, there is in principle no "correct" angle. I should have said correct angle given the initial conditions (of spin and precession).

One day I will record in slow motion all the different throws.
« Last Edit: July 05, 2022, 09:14:02 PM by ta0 »
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ortwin

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Re: Mechanics of the throw flip
« Reply #33 on: July 06, 2022, 03:04:02 AM »

Still not sure that we think we think the same way of the irrelevance of the angle for the precession rate under certain approximations.
Here is statement that says what I meant that I found online by a quick search here.






But of course especially in the first phase the fast top approximation is not holding.
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