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Author Topic: How Is The Absolute Centre Of A Spinning Top Still ?  (Read 2836 times)

Offline neilep

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Wocha Peeps,

As a sheepy, I of course just luff to play with spinning tops !..spinning tops are my all time favourite spinny things that spins and has pretty colours and stuff !

look here's mine....




Nice eh ?  being spun again next Tuesday !


Is this true ?..that the absolute centre of the spinning top is stationary when the top is spinning ?...how can that be ?...maybe I heard wrong eh ?


Correct answers get to play with my spinning top with me !...YAYYYYYYYYY !!



Thank ewe for your kind consideration in this matter.


hugs  & shmishes !


mwah mwah mwah !



neil
I have Something Ewe Can Spin On ! *fnarr*
xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx


 

lyner

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How Is The Absolute Centre Of A Spinning Top Still ?
« Reply #1 on: 31/03/2009 00:01:33 »
That's a top question Neil, my boy.
What do you mean by the centre?
It's all spinning, of course and it will also be precessing / wobbling (it axis will be tracing out a narrow cone) because of the 'moment' caused by its weight pulling down and because the axis isn't perfectly vertical. (this is very violent just before it runs down and finally falls over).
The only bit that will be just spinning will be the point in contact with the ground - it's stuck there!
Now sit on that and spin.
Weeeeeeeee!
 

Offline DoctorBeaver

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How Is The Absolute Centre Of A Spinning Top Still ?
« Reply #2 on: 31/03/2009 08:28:08 »
Strangely enough I was musing over something similar last week (it may even have been Tuesday), but I was thinking about rotating black holes.

The further you are from the axis, the faster you will be travelling. It follows, then, that the closer to the axis you are, the slower you travel. At the very centre of the axis there must be a point of zero size that isn't moving. [:o)]
 

lyner

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How Is The Absolute Centre Of A Spinning Top Still ?
« Reply #3 on: 31/03/2009 09:52:56 »
That pre-supposes that they are rigid, of course.
Would the individual nuclei be bound together?
 

Offline DoctorBeaver

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How Is The Absolute Centre Of A Spinning Top Still ?
« Reply #4 on: 31/03/2009 19:12:48 »
How could you get nuclei in a point of zero size unless they are also zero size?
 

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How Is The Absolute Centre Of A Spinning Top Still ?
« Reply #4 on: 31/03/2009 19:12:48 »

 

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