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Re: the impossible wheel

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Odd Bodkin wrote:

> RichD <r_delaney2001@yahoo.com> wrote:
>> On April 21, Thomas 'PointedEars' Lahn wrote:
>>>>> The tire, over the contact interval, works as planned:
>>>>> it doesn't slide, relative to the road. Which means it's
>>>>> at rest, relative to the road.
>>> 
>>>> No, it is not. Instead, it would remain at rest relative to the road if
>>>> it slid completely and would not “flatten at the bottom”.
>>> 
>>> I can see that this wording, in which I attempted to interpret and adopt
>>> "RichD’s" (wrong) definition of “at rest relative to …” was confusing.
>>> Just assume that I did not write that, and assume that I meant the same
>>> as I wrote and meant subsequently:
>>> Neither a wheel that is rolling nor a wheel that is sliding is ever at
>>> rest relative to the road, because both are kinds of motion.
>> 
>> You attempt to correct yourself.
>> Full credit.
>> 
>> But you still miss the point.
>> All you have done is assert that a bicycle travels forward. duh
>> 
>> We have:
>> i)  The bicycle travels along the road.
>> ii)  It accomplishes this because it's in contact with the road.
>>      (a bike in midair doesn't go far)
>> iii)  The part in contact with the road - the flat track - doesn't
>>      slide; i.e. NO MOTION RELATIVE TO THE ROAD
>> 
>> Thus we see a contradiction.  That defines a paradox.
> 
> There’s no contradiction.
> 
> The CENTER of the wheel travels relative to the road.

Yes.

> The BOTTOM of the wheel does not travel relative to the road.

I do not think it is helpful to introduce ill-defined concepts like ”bottom 
of the wheel”.  It only leads to misconceptions such as the following:

> The TOP of the wheel travels even faster than the center of the wheel,
> relative to the road.

If the “bottom” does not travel relative to the road, then neither does
the “top”.  If what you say were possible, if you were using a consistent 
conceptual framework, then the wheel would have to disintegrate as it is 
rotating.

Your latter statement only makes sense in a different conceptual framework, 
namely when we consider a point on the wheel that is orbiting the center of 
the wheel as the wheel is turning.  For example, a marker on the tire.  And 
then, of course, there is no difference between the speed of a marker on the 
bottom of the tire and one on the top, as the marker on the bottom will 
cyclically become one on the top and vice-versa.


PointedEars
-- 
Q: Where are offenders sentenced for light crimes?  
A: To a prism.

(from: WolframAlpha)

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Re: the impossible wheel Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2022-04-21 19:29 +0200
  Re: the impossible wheel RichD <r_delaney2001@yahoo.com> - 2022-04-21 12:11 -0700
    Re: the impossible wheel Odd Bodkin <bodkinodd@gmail.com> - 2022-04-21 19:18 +0000
      Re: the impossible wheel Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2022-04-21 22:03 +0200
      Re: the impossible wheel RichD <r_delaney2001@yahoo.com> - 2022-04-22 12:36 -0700
        Re: the impossible wheel Odd Bodkin <bodkinodd@gmail.com> - 2022-04-22 19:40 +0000
    Re: the impossible wheel Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2022-04-21 21:53 +0200
  Re: the impossible wheel Sam Kaloxylos <neeo@kzynutyj.ye> - 2022-04-21 20:36 +0000
    Re: the impossible wheel Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2022-04-22 00:39 +0200
      Re: the impossible wheel Sam Kaloxylos <neeo@kzynutyj.ye> - 2022-04-21 22:50 +0000
        Re: the impossible wheel Paul Alsing <pnalsing@gmail.com> - 2022-04-22 06:47 -0700
          Re: the impossible wheel Kye Egonidis <qliz@xuelxjxk.io> - 2022-04-22 21:30 +0000
      Re: the impossible wheel snipeco.2@gmail.com (Sn!pe) - 2022-04-22 01:18 +0100

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