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Re: Rotating Ring

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On 11/02/2016 12:51 PM, sepp623@yahoo.com wrote:
> In a rest frame there is a circular ring that is at rest.  If another
> inertial reference frame is moving with velocity V say along the
> x-axis of the rest frame, that moving frame measures this circular
> ring to be oval shaped due to Einstein's length contraction.
>
> Now if this rest frame has a circular ring that has an angular
> rotation velocity of V, the moving frame has zero instantaneous
> velocity with with the top arc of the ring and has a velocity about
> 2V with respect to the bottom arc of the ring. If we make the ring
> diameter very, very large so that centrifical forces are negligible,
> using Einstein's length contraction concept why does the moving frame
> still measure the rotating ring to be the same symmetrical oval shape
> as when the ring is not rotating?  Why doesn't the moving frame
> measure a different length contraction at the top arc than it
> measures for the bottom arc resulting in a shape that is not
> symmetrical about the x-axis?

Oh goody, Seppala's back.

The rotating ring has other relative velocity components, which you're 
casually ignoring. Before you can find your hoped for contradiction[*], 
you have to show that taking those other velocities into account doesn't 
lead to the oval shape. Given your demonstrated lack of mathematical 
competence, I doubt you're capable of that.

So far, you have nothing.

Sylvia.

[*] This isn't stated, but it's always what Seppala is about.

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Rotating Ring sepp623@yahoo.com - 2016-02-10 17:51 -0800
  Re: Rotating Ring Henry Wilson <HGW@home.com> - 2016-02-11 08:24 +0000
    Re: Rotating Ring JanPB <filmart@gmail.com> - 2016-02-11 01:30 -0800
      Re: Rotating Ring Muddy Shoes <shoes@muddyshoes.org> - 2016-02-11 13:46 +0000
      Re: Rotating Ring Henry Wilson <HGW@home.com> - 2016-02-11 15:51 +0000
  Re: Rotating Ring Sylvia Else <sylvia@not.at.this.address> - 2016-02-11 21:49 +1100
  Re: Rotating Ring Tom Roberts <tjroberts137@sbcglobal.net> - 2016-02-14 17:12 -0600

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