Re: Newbie query: why required weight?

["Robert Morris" <bobmorris@rmci.net>]

Truman:

You must allow for my less than exact science. When I was young and at your
age physics was something you took when you were constipated!!!

Bob Morris
Morris Endurance Enterprises
Boise, ID

----------
> From: Truman Prevatt <truman.prevatt@netsrq.com>
> To: bobmorris@rmci.net
> Cc: ridecamp@endurance.net
> Subject: Re: Newbie query:  why required weight?
> Date: Thursday, September 03, 1998 2:22 PM
> 
> To be percise it is not a question of "energy" it is a question of work. 
For
> a mass moved up against the amount of work is Fd, where F is the force of
> gravity =mg m is the mass and g is the acelleration of gravity.  The path
a
> horse travels is not parallel to the ground - but more a series of arcs
as you
> stat,e Bob.  On each arc  the horse is required to perform work.  Since
the
> work is proportiional to the mass, the more mass the more required work
on the
> same arc.  The total amount of work required is the sum of the work of
each
> arc.
> 
> There are two interesting things that fall out.  First a horse carrying
more
> weight is requied to do more work.  The second thing is the higher the
apex of
> the arc is off the ground, the more work required to tranverse the arc. 
This
> tells you that a horse with a long low gait does less work to go a given
> distance than a horse with a more "antimated"anima - high hang time gait.
 So
> the daisy clipper will need to do less work to cover the same distance.
> 
> I would be pretty simple to calcualte the difference the enegy required
for
> riders of different mass.  Probably as big a factor is the proportion of
the
> rider's mass to the horses mass.  A 400 kg horse carrying a 150 kg rider
will
> have to expend proportionally more work than a 500 kg horse carring a 100
kg
> rider.
> 
> That is the physics - but I will allow others to bebate the merits of
> heavyweight vs feather weight.
> 
> Truman
> 
> 
> 
> Robert Morris wrote:
> 
> > Joe & Ride camp:
> >
> > You state:>>> Sorry, Bob, but your physics is off.  Energy is only
expended
> > moving a
> > > mass against resistance (such as gravity).  It takes more energy to
> > > *lift* a given weight a given height, but not to move it
horizontally.
> > > All else being equal it takes no more energy to move 200 pounds one
> > > *level* mile than to move 100 pounds one level mile.>>>
> >
> > This is absolutely correct but the horse in creating impulsion must
lift
> > the weight, total weight animal and rider, into the air and then push
it
> > forward so the factor of gravity, the overcoming of the movement from
> > static to dynamic state and the like are repeated over and over. Then
you
> > have also introduced the factor of elevation change no matter how
slight.
> > So there is a very distinct "lifting a given weight a given height".
That
> > weight is the factor that brings forth the necessity for setting some
> > standard such as the minimum 165 lb criteria.
> >
> > <
> 
> 
> --
> Truman Prevatt
> Brooksville, FL
> 
> Mystic “The Horse from Hell” Storm
> Rocket a.k.a. Mr. Misty
> Jordy a.k.a. Bridger (when he is good)
> Danson Flame
> 
>