Re: Engineering Newsletter

[Steve VanDevender <stevev@efn.org>]

KellySt@aol.com writes:
 > ReplyFrom : Timothy
 > ReplyTo   : Kelly
 > Subject   : Humans and stairs
 > 
 > >Hold your arm out to you side.  Tell me it takes no effort (energy) to hold
 > >it there.
 > 
 > >> Even if I could convince you that it took no energy to keep
 > >> it there, you would probably say that the only possibility
 > >> was that my feet got colder.
 > 
 > Don't bother.  I refused to get into an argument over levitating arms.
 > 
 > >> Does it TAKE energy to walk down the stairs or does it GIVE energy?
 > 
 > Actually both take energy since your accelerating and decelerating masses of
 > your body.  Though obviously going down you don't need to bost yourself up a
 > gravity/potential energy well.

Tell me this, Kelly.

Given a rod of mass m and height h, standing vertically in a
uniform gravitational field that produces acceleration g, what is
the power in watts of heat energy dissipated by the rod?  I'll
also accept a formula that gives the dissipation of an
infinitesimal element at the bottom of the rod; it would be
sufficient for determining the power dissipated by any section of
the rod by integrating the formula over that section.  Pointers
to experiments that have been done to demonstrate this effect
would also be helpful in convincing me that it's real.

I'm also curious about whether you'd draw a distinction between
that rod standing in a gravity field and the same rod clamped
horizontally in a vise -- in either case the rod is under
compression forces, but the rod clamped in a vise is not getting
its compression from the gravity field.  Does the rod in the vise
also dissipate heat for as long as it's under compression?  Why
or why not?  If it does, where does the energy come from, and
what is the relationship between the tension or compression and
the heat dissipated by the rod?

Like Timothy, I'm not doing this to make fun of you.  You are
stating an opinion that is at odds with accepted laws of physics,
at least as we understand them.  If your belief that standing
structures dissipate heat because of tension or compression
forces has any truth, then it should be possible to demonstrate
the effect experimentally and produce a theory that explains the
effect.