Re: Feeling Acceleration

["A. R. Marlow" <marlow@beta.loyno.edu>]

On Tue, 8 Apr 1997, John D. Sample wrote:

> ...
> So I might describe the situation as:
>
> net force-> acceleration ->internal stresses/fluid displacements
>
> which are felt in the pit of my stomach, inner ear and other places.  I
> *suppose* we could leave acceleration out, but without it---if the force on
> my feet is balanced by some other force---the sensation is entirely
> different.
> ...

I wouldn't really advocate leaving acceleration out  --  it's a very real
effect of forces and pressures  -- it's just not what we sense.
Everything you have pointed out is fully explained by our ability to sense 
the dynamical quantities force, pressure, pressure gradient, whether or
not any acceleration happens to be present relative to some frame of
reference.  Pinch yourself and hold it steady so there is no relative
acceleration involved, and you surely feel it.  To postulate that we have
an additional ability to sense (certain cases of) the kinematical
quantity acceleration goes beyond anything I have experienced.  

A. R. Marlow                          E-MAIL:  marlow@beta.loyno.edu
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