|
|
Re: Introducing the United (fps) System
Posted:
Apr 23, 2000 4:05 PM
|
|
gandg@snet.net wrote:
> In a previous article, Jeffrey Gauch <firstname.lastname@colostate.edu>
> writes:
> >
> >
> >gandg@snet.net wrote:
> >
> >> In a previous article, <glhansen@steel.ucs.indiana.edu> writes:
> >> >In article <01bfabdd$d185eb40$LocalHost@default>,
> >> >Donald G. Shead <u10889@snet.net> wrote:
> >> >>
> >> >>This post is to tentatively anounce a new United foot-pound-second
> system
> >> >>of weights and measures; uniting the _three_ fundamental quantities of
> >> >>science and mechanics:
> >> >>
> >> >>This system unites LENGTH [distance in Space], FORCE, including weight
> >> >>(force) [physical thrust, and the heaviness of Matter] with DURATION
> >> >>[periods of continuously passing Time]. This should create a better
> >> >>understanding of the physical phenomena involved in the mechanics of
> force
> >> >>and the changes in motion that it causes, as well as that of weighing
> and
> >> >
> _Notice_ that: "This should create a better understanding of the physical
> phenomena involved in the mechanics of force and the changes in motion that
> it causes, as well as that of weighing..." This "united system" is not
> applicable to relativistic phenomena: Bending and stretching "space-time",and
> black holes are a lot of hooey anyway! As is the idea of 'action at a
> distance'; which even Newton denied.
Who gives a flying poobah what Newton thought? His biggest achievement in life was
to die a virgin. And why the hell would we be interested in anything that's only
useful at the surface of the earth? You're system breaks down right outside the
atmosphere.
>
> >> >I really don't think you'll be doing freshman physics students any favors
> >> >by replacing F=ma with F=Wa/g.
> >> >
> >> Why do you say that? Not only does this eliminate f=ma, but it also
> eliminates
> >> w=mg:
> >>
> >> f = wa/g incorporates both of them: They'll be glad in it; once their
> prof's.
> >> explain that this is easier to understand, remember and use when
> >> algebraically transposed:
> >>
> >
> >except in the a problem like "what force is required to accelerate a 10lb
> object
> >at 3 ft/sec^2 in space?" dollars to doughnuts some student will think that
> since
> >it's in space g=0
> >
> >>
> >> As (f/w) = (a/g); it's easy to see that force (f) is to weight (force) [w],
> as
> >> acceleration (a) is to free fall (acceleration) [g]:
> >>
> >> As w/g = f/a; it's easier to see that weight (force) [w] is to free fall
> >> (acceleration) [g], as net force (f) is to acceleration (a): They are
> >> _equivalent_!
> >>
> >
> >that's becuase w=mg is just a special case of f=ma.
> >
> Uh-huh.
What don't you get about it? Weight is a force, g is an acceleration.
> >>
> >> This equivalency formula (w/g = f/a) contains all of the basic concepts
> needed
> >> for:
> >>
> >> f = wa/g
> >> w = fg/a
> >> a = fg/w
> >> g = wa/f
> >>
> >
> >what about momentum? you really want p=wv/g as opposed to p=mv??
> >
> What's wrong with it?
beside the fact you've added a term? If we were to use your system most physics
equations would have a W/g term floating around. Since it would be heavily used
someone would give it a special name and symbol...oh, wait, they've done that,
it's called the mass, m.
>
> >>
> >> Add the fact that (average) acceleration (a) is a change in velocity
> (Vt-Vi)
> >> during time (t); so that a = (Vt-Vi)/t; your on your way kids...
> >>
> >> Mass is superflous: But it's interesting to note that "Gravitational Mass"
> >> (w/g) is equivalent to "Inertial Mass" (f/a)!
> >>
> >
> >Mass is not superflous, weight can be zero (i.e. acceleration is 0), but
> there's
> >always mass. (you might not be able to measure it, but it's still there.
> >
> What good is mass if you can't measure it? To be "mass", which is a measure of
> the quantity, and/or inertia of an object and/or body of matter, these
> 'properties' must be measurable: If a mass _exists_, here, there,or
> _anywhere; there are two ways that I know of to 'measure it':
>
> Mass is a measure of the _inertia_ of a _quantity_ of matter; which here on
> Earth is most easily measured by placing a mass (object, and/or body) of
> (accumulated) material substance on a scale - one that measures force, not an
> equal arm balance that compares the weight _and_ mass _two_ masses - the
> weight (force) [w] as indicated by the scale, divided by the free fall
> acceleration (g) here at Earth's surface is its "gravitational mass": At a
> location where the free fall acceleration of a mass is unknown, we can
> determine its "inertial mass" by exerting a _net_ force (f) on it, and
> measuring the acceleration (a) that it causes. This net force (f), divided by
> the acceleration (a) that it causes is its _inertial mass_; which is
> 'equivalent' to its _gravitational mass_.
>
Or you could spray anitmatter at it until energy stops coming out, measure the
total energy emitted, divide by 2, and divide by c^2. But you've already said it
doesn't apply to relatavistic systems, so it's useless in the real world.
--
"Did I remember to feed my cat?"
-Erwin Schrodinger
|
|
