Re: Mechanical, chemical and heat energy

[Niccolai Murphy <niccolai_m@yahoo.com>]

I should know better than to get into this with a methematician!

Regarding surface area, not strictly true. Weight is proportional to
volume which would be a approimated by a cubic function of some
notional dimension (especially if we are discussing a spehrical
horse). Whereas surface area would be approximated by a square
function of that same dimension. So a lighter horse should have a
higher surface area to weight ratio than a heavier horse.

Also, energy is conserved if you take the boundary of the experiment
far enough away from the horse. If you draw the boundaries around the
horse than energy is lost from the system, as you say in the form of
heat, noise, etc. The horse itself must be a highly damped system
leading to huge damping losses in the form of heat. If damping is a
function of the product of force and velocity then the heavier horse
without payload would tend to loose more than the smaller horse. So it
interesting to see that the rider weight seems to be represented by an
uncoupled equation.

> Energy is conserved.  If it takes X cal to mover a 500 kg horse or a
400
> kg horse with a 100 kg rider, then Y cal of heat have to be
dissipated. 
> A 500 kg horse has 25% more surface area from which to dissipate this
> excess heat.  Hence in conditions where heat dissipation is
compormised
> such that the 500 kg horse was at its limit of heat dissipation, the
400
> kg horse will be at a serious disadvantage.  
> 

Aren't you talking potential here? mechanical work must include
friction - non conservative.

> I believe any study, to be comprehensive enough, to be of PRATICAL use
> needs to take into account the entire engery chain - the mechanical
work
> required (easy to calculate since gravity, the primary force, is
> conservative), the chemical enqergy + heat energy requred for this
work
> to be done and the dissipation of the heat energy.  The heat energy
> being from the chemical reactions to produce the mechanical energy
which
> results from an efficient conversion between chemical and mechanical
> energy.  This has to be then balanced with the heat dissipation side
of
> the equation.  I believe that ignoring this issues in the design of
> experiment is ignoring a significant factor that must be considered to
> get a realistic picture.
> 
> Truman
> 

Hey, is it my imagination or have you been collecting more horses?

> -- 
> Truman Prevatt
> Mystic “The Horse from Hell” Storm
> Rocket a.k.a. Mr. Misty
> Jordy a.k.a. Bridger (when he is good)
> Danson Flame - hey dad I'm well now and ready to go!
> 
> Brooksville, FL
> 
> 

==
Nicco Murphy - Poway, San Diego, CA


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