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Re: Relativistic train on relativistic wheels

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W dniu środa, 26 października 2016 00:23:02 UTC+2 użytkownik JanPB napisał:
> On Tuesday, October 25, 2016 at 12:23:12 PM UTC-7, al...@interia.pl wrote:
> > W dniu wtorek, 25 października 2016 20:06:16 UTC+2 użytkownik JanPB napisał:
> > > On Tuesday, October 25, 2016 at 10:44:55 AM UTC-7, al...@interia.pl wrote:
> > > > W dniu piątek, 21 października 2016 11:15:52 UTC+2 użytkownik mlwo...@wp.pl napisał:
> > > > > The wheels of a train have l diameter.
> > > > > The train accelerates to 0.99c relative to ground observer.
> > > > > 1)Is it possible?
> > > > 
> > > > a speed of the top of a rotating wheel is:
> > > > 
> > > > --> wr
> > > > O---> v
> > > > <-- -wr
> > > > 
> > > > -------> 2v 
> > > > ----> v - a speed of the center of the wheel
> > > > >0
> > > > 
> > > > thus a limit for a speed of the wheel is 0.5c
> > > 
> > > Incorrect. The original question was framed within relativity. You are
> > > using Newtonian mechanics.
> > > 
> > > --
> > > Jan
> > 
> > Using the real Lorentz contraction,
> > for v = c:
> > 
> > |---> c
> > |
> > |---> c
> > |
> > |---> c
> > ============== some road
> > 
> > the all point of the circle moves at c.
> > 
> > The top speed is not 2c because there is the extremal contraction...
> > dL/dt = -c.
> > 2c + -c = c
> > 
> > similarily the point on bottom:
> > 0 + c = c.
> > 
> > because at this point the expansion is extremal: dL/dt = +c,
> > etc.
> > 
> > Look at a middle point:
> > the speed is usualy: sqrt(v^2 + (wr)^2) = sqrt2 v;
> > 
> > but in this stupid example it is equal to c too,
> > because now the contraction is infinite,
> > thus the central part of the wheel is infinitely dense:
> > the mass just flows from this point with zero speed, but with infinite density:
> > m * v = const.
> 
> Before answering your mistakes, let me ask you this elephant in the room
> type question:
> 
> Do you really think, even for a split second, that you CAN be correct here?
> You know what this would imply, don't you.
> 
> (Just testing if you're simply too far gone or it's merely a language
> problem.)
> 
> --
> Jan

The problem is infinitely too hard for you,
and for any other childern in the sci.

More! This problem is over the actual science in general...
This's a type of PDE-problem in fact, not any stupid cinematics.

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Relativistic train on relativistic wheels mlwozniak@wp.pl - 2016-10-21 02:15 -0700
  Re: Relativistic train on relativistic wheels Sylvia Else <sylvia@not.at.this.address> - 2016-10-21 22:37 +1100
    Re: Relativistic train on relativistic wheels mlwozniak@wp.pl - 2016-10-21 06:43 -0700
      Re: Relativistic train on relativistic wheels Dirk Van de moortel <dirkvandemoortel@hotspam.not> - 2016-10-21 16:36 +0200
        Re: Relativistic train on relativistic wheels Jim Barthel <jimbart@portlanportal.info> - 2016-10-21 15:00 +0000
          Re: Relativistic train on relativistic wheels Dirk Van de moortel <dirkvandemoortel@hotspam.not> - 2016-10-21 17:58 +0200
          Re: Relativistic train on relativistic wheels JanPB <filmart@gmail.com> - 2016-10-21 10:31 -0700
        Re: Relativistic train on relativistic wheels Sylvia Else <sylvia@not.at.this.address> - 2016-10-24 11:24 +1100
          Re: Relativistic train on relativistic wheels Dirk Van de moortel <dirkvandemoortel@hotspam.not> - 2016-10-26 22:27 +0200
  Re: Relativistic train on relativistic wheels Alan Folmsbee <omnilobe@gmail.com> - 2016-10-21 09:48 -0700
    Re: Relativistic train on relativistic wheels abu.kuanysh05@gmail.com - 2016-10-24 11:06 -0700
      Re: Relativistic train on relativistic wheels mlwozniak@wp.pl - 2016-10-24 23:31 -0700
  Re: Relativistic train on relativistic wheels alsor@interia.pl - 2016-10-25 10:44 -0700
    Re: Relativistic train on relativistic wheels JanPB <filmart@gmail.com> - 2016-10-25 11:06 -0700
      Re: Relativistic train on relativistic wheels alsor@interia.pl - 2016-10-25 11:35 -0700
        Re: Relativistic train on relativistic wheels JanPB <filmart@gmail.com> - 2016-10-25 12:13 -0700
          Re: Relativistic train on relativistic wheels alsor@interia.pl - 2016-10-26 07:23 -0700
      Re: Relativistic train on relativistic wheels alsor@interia.pl - 2016-10-25 12:23 -0700
        Re: Relativistic train on relativistic wheels JanPB <filmart@gmail.com> - 2016-10-25 15:22 -0700
          Re: Relativistic train on relativistic wheels alsor@interia.pl - 2016-10-26 07:12 -0700

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