I heard a spin-top in a perfect vacuum would stay spinning

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Discussion Overview

The discussion centers around the behavior of a spinning top in a perfect vacuum, particularly whether it would continue to spin indefinitely without falling due to gravity. Participants explore concepts related to friction, gravitational effects, and the implications of spinning at high speeds.

Discussion Character

  • Exploratory
  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • Some participants propose that a spinning top in a perfect vacuum would spin indefinitely due to the absence of friction or other forces acting on it.
  • Others argue that the gravitational field would still affect the top, potentially causing it to slow down or fall if it were in contact with a surface.
  • A participant suggests that a top in free fall would not slow down due to gravity unless it touches something else, such as the ground or air.
  • There is a contention regarding the concept of spinning at the speed of light, with some participants asserting that nothing can spin at that speed.
  • One participant expresses confusion about the implications of gravity on the spinning top, questioning how it could remain spinning without falling.
  • Another participant attempts to clarify that while gravity affects the top, it does not necessarily mean the top will slow down unless it interacts with another object.
  • A later reply introduces a complex idea about photons and gravity, suggesting that the top's behavior could be influenced by the presence of photons and space pull, but this is met with skepticism.

Areas of Agreement / Disagreement

Participants do not reach a consensus on whether a spinning top in a perfect vacuum would spin indefinitely or how gravity would affect its motion. Multiple competing views remain, with some participants supporting the idea of indefinite spinning while others emphasize the role of gravity and friction.

Contextual Notes

Limitations include unclear definitions of "perfect vacuum," assumptions about the effects of gravity on spinning objects, and unresolved discussions about the implications of spinning at high speeds.

SciencePerson
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Ok I heard that a very fast spinning top, in a perfect vacuum, on Earth, would stay spinning forever, and I suppose it would in the middle of the vacuum without falling, because spinning at lightspeed means it can't move 1 down, so if the speed in this top stays in it, then it could avoid falling and slowing~

Help :O
 
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SciencePerson said:
Ok I heard that a very fast spinning top, in a perfect vacuum, on Earth, would stay spinning forever, and I suppose it would in the middle of the vacuum without falling
A top floating in a perfect vacuum will indeed spin forever, because there's no friction or other force to slow it down. In fact, right now you're standing on of those tops: The Earth has been spinning on its axis for some billions of years now, and looks to be good for many more.

But...
because spinning at lightspeed means it can't move 1 down, so if the speed in this top stays in it, then it could avoid falling and slowing~
This makes no sense at all. Nothing spins at the speed of light.
 
Yes the Earth stays spinning, but, the top is in the field of gravity! It may slow down then from pull! And fall downwards...
 
SciencePerson said:
Yes the Earth stays spinning, but, the top is in the field of gravity! It may slow down then from pull! And fall downwards...

The mere presence of a gravitational field doesn't affect the spin of the top. However, if the top is touching the ground in any way, there will be some small amount of friction at the pivot point, and that friction will slow the top. If you were to put the top into orbit around the earth, it would still be in the Earth's gravitational field, but it could fall freely without every touching the ground and then there would be no friction to slow it (except that space is not quite a perfect vacuum).
 
Wait wait wai wa hate a moment :D...are you saying gravity won't affect it just because satellites don't fall, because those are different! They move left whhhille moving down! Like this - >^>^>^>. . .BUT the spinning top may go down by gravity, plus slow by the pull...unless you (somehow) [how?] know it won't.
 
That's not what Nugatory is saying. He's saying that a top in free fall (under the effect of gravity) won't slow down just because gravity is acting on it. It must touch something else in order to slow down. Your falling top would start to slow down when it entered the Earth's atmosphere and began to interact with the air.
 
So a planet stays spinning, and if it doesn't slow by any pull, then it wouldn't fall...wait......if the fast spin top is in the exact middle of a perfect vacuum on Earth, it stays spinning, and no fall, yet it does, and only it does for the fall...ArhhhrRR!...I'll think about this later, busy at the moment...
 
SciencePerson said:
So a planet stays spinning, and if it doesn't slow by any pull, then it wouldn't fall

SciencePerson said:
.if the fast spin top is in the exact middle of a perfect vacuum on Earth, it stays spinning, and no fall,

What do you mean by 'fall'? The top (and the planet) are still affected by gravity and are still pulled down. A top in a vacuum here on Earth would stay spinning a little longer than a top outside in the air, but not forever since friction from the ground still acts on the tip.
 
What I figured out is this:

If a spinning top in a perfect vacuum could avoid falling, it will stay spinning forever because the moving photons and therefore moving particles stay in it, but the reason it falls by gravity is because it gets photons OR space pull without being touched by atoms to take away the top's photons and so it also moves down, and may not fall if at lightspeed since no more room is left because the added photons or space pull by gravity don't affect the already-filled-spaces-photons in it~

If you want I can write this out clearer...
 
Last edited:
  • #10
That's just utter nonsense. Thread locked.
 

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