Re: Train Physics Problem

From	Fabian Russell <root@localhost.localdomain>
Newsgroups	sci.physics
Subject	Re: Train Physics Problem
Date	2015-11-04 23:33 +0000
Organization	NewsGuy - Unlimited Usenet $23.95
Message-ID	<pan.2015.11.04.23.33.56@localhost.localdomain> (permalink)
References	<pan.2015.11.03.02.06.31@localhost.localdomain> <n1agtm$abd$1@speranza.aioe.org> <Md7_x.50705$I83.43968@fx04.iad> <pan.2015.11.03.18.53.50@localhost.localdomain> <Adw_x.8$lf7.5@fx29.iad>

Show all headers | View raw

On Wed, 04 Nov 2015 18:08:16 -0500, benj wrote:

> So there 
> is this highly complex economic relationship between ALL the factors 
> including wheel inertia, wheel rolling losses, metal wear and probably 
> much more.
> 

Sure there are some complications.  But I cannot ever imagine that the
prime factor would be anything other than hardness and rolling friction.

I have two hand trucks, similar to the lower left of the examples
on this page:

http://adamsindustrialsupply.com/HandTrucks.html

One hand truck has pneumatic tires (inflatable), and the other has
hard solid rubber polymeric tires.

Putting the same very heavy load on both hand trucks, and pushing both
on the same concrete surface, reveals a fantastic difference.  On pneumatic
tires, the load requires tremendous force to push.  With the hard rubber,
pushing the load is nearly effortless.  Unless one has performed this exercise,
it is difficult to even imagine the extreme difference.

So if I were a railroad engineer, I'd say screw all other considerations
and give me hardness.

Thread

Train Physics Problem Fabian Russell <root@localhost.localdomain> - 2015-11-03 02:05 +0000
  Re: Train Physics Problem Fabian Russell <root@localhost.localdomain> - 2015-11-03 02:31 +0000
    Re: Train Physics Problem Fabian Russell <root@localhost.localdomain> - 2015-11-03 02:38 +0000
    Re: Train Physics Problem gillyshin <spectrum8@sincity.info> - 2015-11-03 04:38 +0000
      Re: Train Physics Problem gilber34 <fafa@invalid.com> - 2015-11-02 22:58 -0600
        Re: Train Physics Problem Fabian Russell <root@localhost.localdomain> - 2015-11-03 05:22 +0000
  Re: Train Physics Problem Odd Bodkin <bodkinodd@gmail.com> - 2015-11-03 08:38 -0600
    Re: Train Physics Problem Fabian Russell <root@localhost.localdomain> - 2015-11-03 18:19 +0000
      Re: Train Physics Problem Odd Bodkin <bodkinodd@gmail.com> - 2015-11-03 15:00 -0600
        Re: Train Physics Problem Fabian Russell <root@localhost.localdomain> - 2015-11-03 21:22 +0000
          Re: Train Physics Problem Odd Bodkin <bodkinodd@gmail.com> - 2015-11-03 16:55 -0600
            Re: Train Physics Problem Fabian Russell <root@localhost.localdomain> - 2015-11-03 23:19 +0000
        Re: Train Physics Problem Fabian Russell <root@localhost.localdomain> - 2015-11-03 21:31 +0000
          Re: Train Physics Problem Odd Bodkin <bodkinodd@gmail.com> - 2015-11-03 17:17 -0600
    Re: Train Physics Problem benj <none@gmail.com> - 2015-11-03 13:41 -0500
      Re: Train Physics Problem Fabian Russell <root@localhost.localdomain> - 2015-11-03 18:53 +0000
        Re: Train Physics Problem benj <none@gmail.com> - 2015-11-04 18:08 -0500
          Re: Train Physics Problem Fabian Russell <root@localhost.localdomain> - 2015-11-04 23:33 +0000
      Re: Train Physics Problem Odd Bodkin <bodkinodd@gmail.com> - 2015-11-03 15:10 -0600
        Re: Train Physics Problem Fabian Russell <root@localhost.localdomain> - 2015-11-03 21:48 +0000
          Re: Train Physics Problem benj <nobody@gmail.com> - 2015-11-04 02:45 -0500
  Re: Train Physics Problem "reber g=emc^2" <herbertglazier0@gmail.com> - 2015-11-03 09:19 -0800
    Re: Train Physics Problem "reber g=emc^2" <herbertglazier0@gmail.com> - 2015-11-04 15:15 -0800

csiph-web