Re: Apparent weight

[David Bowman <dbowman@tiger.gtc.georgetown.ky.us>]

Regarding Rick's comment:
> For me, the justification for dealing the 'apparent' weight is that it helps
> us deal with a whole range of _perceived_ forces--internally experienced by
> people.  We tend to interpret many forces _backwards_ and if we keep weight
> as the 'downward' pull of the earth (or other large body) then weight is
> also one of these backwards forces.

I don't know about you, but I don't think I can perceive any forces of any
kind in terms of a physical sensation.  I do perceive relative distensions of
various parts of my body wrt each other, though.

>                                    The apparent weight is then the force
> that we perceive (to be our weight).  To be sure, in _most_ cases, this is
> what the bathroom scale reads, but what the bathroom scale reads is an
> UPWARDS force.

My bathroom scale measures the component of compressive strain oriented along
the axis perpendicular to its two widest surfaces.  This measurement is
conveniently calibrated in force units via an application of Hooke's law
and the fact the the surface across which the applied stress acts has a
constant area.

>               Don't tell me that isn't going to be confusing to students
> for whom weight has been _defined_ as what the bathroom scale reads but for
> whom the 'sensation' is downward.  Apparent weight is an attempt to deal
> with this discrepency--perhaps not successfully for some, but it works for
> me.  ;-)

I do not understand this.  Are you referring to something going on in the
inner ears of the students or what?

David Bowman
dbowman@gtc.georgetown.ky.us