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TL ADAMS  writes:
> It must be nice, to be able to draw your boundries around one little
> section of the problem and therefore declare the whole industry is
> safe.
> Must be nice.
> And we further draw our little box to only include western
> technology so that the problems of the Soviets and Chinesse are also
> removed.
> Must be nice.
> Yet you lose the battle of public opinion because most people don't
> draw such nice little boundries. When they see a nice multibillion
> clean-up at a little site like Fernald, maybe they don't have your
> distachment to say this is from the "bad" nuclear industry, but we
> are the "good" nuclear industry.
> I am not saying this is fair, hell it may not even be a valid
> preception, but it is a wide-spread preception.  The sins of those
> other nuclear guys may haunt you good guys for many generation.
The real looser is our environment when people shoose fossil fuels
after being scared by the bad implementations in the "eastern" nuclear
industry and the military programs. :-(
Regards,
--
--
Magnus Redin  Lysator Academic Computer Society  redin@lysator.liu.se
Mail: Magnus Redin, Björnkärrsgatan 11 B 20, 584 36 LINKöPING, SWEDEN
Phone: Sweden (0)13 260046 (answering machine)  and  (0)13 214600

MILWARD wrote:
MILWARD  writes
> There are a couple of questions that I have been set as physics homework, and I
> just cannot work them out, and I would be really grateful if YOU know the
> answers to either of them:
> 
> -GO ON! PROVE YOUR GENIUS TO ALL!!-
This kind of provoking is not a very nice way in which ask people to
help you with your homework. That said 
Q: Derive an expression for the kinetic energy of a particle of mass 'm'
which
has momentum 'p'.
Assuming the question is to give the kinetic energy in terms of the
momentum 'p' and mass 'm', proceed as follows:
The kinetic energy of a particle of mass 'm' is defined to be K=(1/2)
mv^2
The moment of the particle is defined to be p=mv --> v=p/m.  Substitute
this expression into the the expression for K --> K=(1/2) m (p/m)^2 =
(1/2) p^2/m.
I'll let the other geniuses give you the rest.
Peter M. Brown

Peter F. Curran wrote:
-> 
-> There are several ways to measure physical time to great
-> degrees of accuracy totally independently of own perception, 
-> and they are more or less in agreement with each other, (but 
-> not necessarily with us).  I therefore feel time  is not
-> effected by our perception of it.  I also don't really feel 
-> that the past, present or future have to have any sort of 
-> meaning other than just "being".
-> 
Mr. Curran has done something to his consciousness that is all too
common today (and perhaps common since language & tools allowed us
to *conceive* of existence objectively).  Imagine slowly awakening
as a babe and discovering first the difference between "me" or "I"
and "it" or "them".  Discovering, in other words, embodiment. Next
comes memory and expectation.  Mama will soon come back, because 
she has here before.  This is time-awareness.  Soon we see it from
the outside (as it were) and believe time is our tool.
At some point, someone measured this movement, this change which
seems to take place sub-atomically and with no small degree of
randomness.  Our crude clocks which *seem* to click with a certain
sort of regularity are not TIME or even its measure.  They are
simply controlled motion.  The alarm?  Awake, my friends.
-- 
Greg Nixon 
"Ya yé, moin nan sang hé!"

Here is my opinion on why we think it is nice for theories to explain
why.  I consider it related Occam's Razor: always choose the simplest
theory which would allow one to predict the observed phenomenon.  I
hypothesize that every explanation why starts the most simplest, or
most comfortable, set of accepted premises which leads one to a
prediction of the observed effect.  Explanations of how don't
necessarily start with a simplest, or most basic set of premises, but
they can and do begin with a set acceptable to the producer.
If you ask a physicist why light does anything, he is likely to point
to Maxwell's equations.  This is, in some sense, the most basic set of
premises used to explain light, at least when thinking classically.
On the other hand, if you ask how light propagates, especially with
some application in mind, a physicist would likely limit the
discussion to the mechanics of wave propagation.  The discussion would
still touch on Maxwell's equations, but they would not be presented as
starting point to understanding the phenomenon.  It is unusual to need
to work out the propagation equations from first principles, and
therefore I would not expect somebody to explain them as such.
To this end, I think that a certain amount of unification and
condensation of the origins of phenomenon is necessary before a theory
becomes acceptable as an explanation why.  However, this boundary
between how and why is very flexible.  I could be wrong, but I think
people are divided on the acceptability of quantum mechanics as the
`why' for quantum effects.  In comparison, I would say that people
usually consider GR to be a very nice explanation why for effects in its
domain.
I really don't see how the concept of why, like the applied idea of
simplicity in the statement of Occam's Razor, can be considered
anything but a human construct.  The universe is run by a theory that
we don't know, so anything we do know is an approximation.  However,
Newton's law's of mechanics are still, and probably always will be,
used to explain why a multitude of effects occur.  Lagrangian
mechanics are arguably derived from a simpler statement, but that
statement doesn't have the same feel of comprehensibility, so it
generally isn't presented as an explanation why.  Lagrangian mechanics
isn't the origin of the phenomenon as the physicist thinks about it,
so it isn't a good explanation why.
Is being simplified enough to explain why a good thing in a theory?
Good or not, it is and always will be looked for in new theories.  I
have yet to hear somebody dispute Occam's Razor as a tool for
identifying useful theories.  There are plenty of ways to explain the
world that require more premises than the currently accepted one, I
suspect that quite a number of them can be patched to explain any new
phenomenon.  They tend to have a crackpot feel to them, and the
simplicity of their premises is the only impartial way I know to
identify them as such.
---
Ben Galehouse
bg2c+@andrew.cmu.edu

Magnus Redin wrote:
>
> 
> The real looser is our environment when people choose fossil fuels
> after being scared by the bad implementations in the "eastern" nuclear
> industry and the military programs. :-(
> 
> Regards,
> 
Other than the fact that I would include the carelessness of the 
early enrichment plants, low-level and mid level storage sites, I'd
pretty much agree with that statement.
I'd also throw in the negligence at three mile, the criminal behavior
that was occuring at site like Zimmer and Marble Hill.  
From my occasion with the industry, it run by a bunch of ex-DOE or DOD
parnoid, you-don't-need-to-know-anything s.o.b's.  I spent too many
years at site remediations and charecterization, fighting for legal
entry, fighting for a minimul compliance with the regulations, to ever
trust the U.S. NPI.  But, I am old, maybe you can convince a younger
generation that things have changed.
I wonder also, if much of the difference in outlooks is the fact that
you are in one of the nordic socalism, and there is just better
co-operation between the government, people, and industry.

In article , mdj@pacific.mps.ohio-state.edu (Matt Jones) wrote:
> Does anyone know of an analysis of the effects of the Alcubierre warp drive
> geometry [M. Alcubierre, Class. Quantum Grav. 11, L73 (1994)],
> ie. redshift/refraction/etc.
No, sorry.
> Barring that, any suggestions on how best to perform such an analysis?
Choose a point in spacetime from which light is emitted, and choose the
direction in which it is emitted.  Then there is a well-defined
procedure for calculating the path of the light ray.  You take
Alcubierre's metric, and solve the (null) geodesic equation given those
initial data.  Look in a general relativity textbook for details on the
math.
-- 
Nathan Urban | nurban@vt.edu | Undergrad {CS,Physics,Math} | Virginia Tech

In article <590bi4$qi0@sjx-ixn3.ix.netcom.com>, odessey2@ix.netcom.com(Allen Meisner) wrote:
> How about this: Since the work done between the acceleration
> gaps is constant if the charge is kept constant, then as the particle
> speeds up the change in velocity will decrease dramatically since the
> plates have less time to act on the particle.
Well, if you know the potential difference across the two plates, the
kinetic energy acquired by transiting them is constant, regardless of
how fast this happens.  But according to relativity, a fixed increase
in kinetic energy makes less and less of a velocity difference as your
velocity increases.
-- 
Nathan Urban | nurban@vt.edu | Undergrad {CS,Physics,Math} | Virginia Tech

To my brethren in biology and physics:
I include you because I'm hoping you will pass on the URL to your off-line
chemistry colleagues. Please encourage them to pass on the URL to their
students.
Thanks. I appreciate your help.
The URL is:
http://dbhs.wvusd.k12.ca.us/ChemTeamIndex.html
I've added the answers to the AP Free Response questions back to 1985.
These are the scoring standards used for the given year, not my own
solutions. Some of you, no doubt, have purchased the AP Chem questions
offered on disk by Harvey Gendeau (sp?). The enclosed solutions are his,
not the readers' of the AP test. My set also have the added advantage of
being free.
I also added some classic papers by Arrhenius and Faraday as well as a
link to Carmen Giunta's site with even more classic chemistry papers.
Although he is not strictly a chemistry person, I did find a picture of
Camilo Golgi on the web and added its address to my photo gallery, way at
the end of the list.
I'm hoping to get 40-50 hours of work this 2 weeks of Christmas vacation
on my tutorials as well as posting National Chemistry Olympiad tests,
which I found out are not copyrighted.
Feel free to make comments or suggestions as you see fit. I'm always in
the market for tips or the most "minor" of error corrections.
John Park
ChemTeam@clubnet.net