HDTenEightyP/NetNews huggingface dataset:
From: john_palkovic@ssc.gov
Newsgroups: sci.misc
Subject: Re: Microwaves in a microwave oven?
Date: 6 Apr 92 15:34:58 GMT
	<1992Mar30.171705.18097@hellgate.utah.edu>
	<1992Mar31.145834.29895@ssd.kodak.com> <Br7wrhUhBfb@lupulus.ssc.gov>
Organization: Medium Energy Booster RF, SSCL

I said:

> Check out the Science and Technology encyclopedia or the Radio
> Engineers Handbook and ref.  therein.

Make the second reference "Reference Date for Engineers: Radio,
Electronics, Computer, and Communications," 7th ed., Edward C.
Jordan, editor, ch. 16.

Adios,

-John
--
john_palkovic@ssc.gov
I joined the League for Programming Freedom -- send mail to john@phc.org
The SSC, the DOE, and the URA are not my mother.
Xref: sparky sci.misc:1040 sci.math:5884 misc.wanted:4943 misc.consumers:10316 misc.education:1849
From: lstowell@pyrnova.pyramid.com (Lon Stowell)
Newsgroups: sci.misc,sci.math,misc.wanted,misc.consumers,misc.education
Subject: Re: A U.S. President and Pythagorean?
Date: 9 Apr 92 15:27:26 GMT
Reply-To: lstowell@pyrnova.pyramid.com (Lon Stowell)
Distribution: na
Organization: Pyramid Technology Corp., Mountain View, CA

In article <1992Apr9.090734.1@scivax.stsci.edu> reinhard@scivax.stsci.edu writes:
>
>Can any one tell me which U.S. President developed
>a proof to the Pythagorean Theorem?
>
    Hopefully all of them with an 8th grade education or better.

    Are you talking about voo-doo geometry or what?  Did one of them
    DISPROVE the theorem?

    PS.  does this have anything to do with consumers?  >:-)
From: bd670@cleveland.Freenet.Edu (Russell I. Dyreng)
Subject: Science Teachers' Organizations Outside the U.S.
Organization: Case Western Reserve University, Cleveland, Ohio, (USA)
Date: Tue, 7 Apr 92 22:12:45 GMT


I am trying to locate groups similar to the National Science 
Teachers' Association (NSTA) in countries outside of the United
States.  I am particularly interested in finding NSTA-type 
organizations in Canada, Western Europe and the Pacific Rim.

If you are aware of the existence of such a group, I would
appreciate you sending me the name and address of the 
organization via e-mail.

Thank you.

Russell I. Dyreng
bd670@cleveland.freenet.edu
From: john_palkovic@ssc.gov
Newsgroups: sci.misc
Subject: Re: Microwaves in a microwave oven?
Date: 6 Apr 92 07:26:30 GMT
	<1992Mar30.171705.18097@hellgate.utah.edu>
	<1992Mar31.145834.29895@ssd.kodak.com>
Organization: Medium Energy Booster RF, SSCL

>>>>> On Tue, 31 Mar 92 14:58:34 GMT, dj@ssd.kodak.com (Dave Jones) said:

Kenneth Tolman and others:
>>>How does a microwave oven make the microwaves?
>>
>>A magnetron tube.  Emits EMR in the specific microwave range to excite
>
>Well...  I am curious as well.  Exactly HOW does it emit the proper EMR?
>(electro magnetic radiation, I assume)
>
>Some sort of induced excitation/relaxation like in a laser?  What is a 
>magnetron tube?  What elements/molecules are at work in what ways?

It is an induced radiation, but not like a laser. Purely classical
physics here.

Dave> [ Describes shape of magnetron]

Dave> What happens then I'm not able to explain in detail, but
Dave> basically the ...

A magnetron (or a klystron) is a device that converts the kinetic
energy of an electron beam into electromagnetic wave energy. They
have many applications (radio, radar, particle accelerators, ...).

Short explanation - accelerated charges radiate. :) 

Longer explanation: I'm too tired right now. This is a lousy medium
for explaining physics anyway. It is a complicated problem. I don't
know of any E&M texts that deal with this.  Among other things, you
have to include the image charges on the walls of the cavity to get
the right answer. What you have is an electron beam interacting
with a system of coupled E&M oscillators.  I would suggest going to
the library (as someone else did). Check out the Science and
Technology encyclopedia or the Radio Engineers Handbook and ref.
therein.

Adios,

-John

--
john_palkovic@ssc.gov
I joined the League for Programming Freedom -- send mail to john@phc.org
The SSC, the DOE, and the URA are not my mother.
Newsgroups: sci.misc
Subject: Re: Solar Collection/Fresnel lenses
From: hbg6@phx.mcd.mot.com (John Schuch)
Date: 13 Apr 92 19:00:32 GMT
Organization: Motorola Computer Group, Tempe, Az.

In article <1992Apr8.195550.7020@hamblin.math.byu.edu> richard@ee.byu.edu (Richard Christensen) writes:
>[stuff deleted]
>Edmund Scientific told me that the only thing that mattered was
>the number of lines per inch.  The lower the better (counter-intuitive
>isn't it).  

Not really if you consider the optimum would be a large regular lens
of the same diameter, that would have 0 lines. ( or 1 depending on
how you look at it )

John
From: ab0kfc@gdt.bath.ac.uk (K F Chow)
Newsgroups: sci.misc
Subject: BMS survey
Date: 6 Apr 92 17:30:13 GMT
Organization: School of Architecture, University of Bath, UK

If you are an undergradate of engineering you may like to
do a questionnaire through email, on the subject "Building
Management Systems". This questionnaire is being done by 
your counterparts at USA, CAN, & UK. Comparison will be 
made between you and them.

If you know nothing about BMS but you know some others may 
do, please pass on the message.

Come and Join the party !!

-------------------------------------------------------------
K.F CHOW                      email : ab0kfc@uk.ac.bath.sl1
School of Architecture &              ab0kfc@uk.ac.bath.gdt
Building Engineering,
Bath University, UK
-------------------------------------------------------------
Newsgroups: sci.misc,sci.math,misc.wanted,misc.consumers,misc.education
From: zaphod@advise.larc.nasa.gov (Lyle D. Sanders)
Subject: Re: A U.S. President and Pythagorean?
Organization: NASA Langley Research Center, Hampton, VA  USA
Distribution: na
Date: Wed, 15 Apr 1992 21:08:03 GMT

In article <181001@pyramid.pyramid.com>, lstowell@pyrnova.pyramid.com (Lon Stowell) writes:
|> In article <1992Apr9.090734.1@scivax.stsci.edu> reinhard@scivax.stsci.edu writes:
|> >
|> >Can any one tell me which U.S. President developed
|> >a proof to the Pythagorean Theorem?
|> >
|>     Hopefully all of them with an 8th grade education or better.
|> 
|>     Are you talking about voo-doo geometry or what?  Did one of them
|>     DISPROVE the theorem?
|> 
|>     PS.  does this have anything to do with consumers?  >:-)


Well, let's see... Ronald Regan was past the 8th grade before the Pythagorean
Theorem was thought of, so it was not him!

And I doubt Jerry Ford could have managed such a task as understanding the
Pythagorean Theorem, let alone prove it, so it was not him!

Richard Nixon MAY have stolen a copy of the proof, does that count?

For the most part, most, if not all, of the recent U.S. Persidents probably
didn't (don't) care about the Pythagorean Theorem.


Just my opinion...


Lyle D. Sanders                      zaphod@answers.larc.nasa.gov
UNISYS Government Systems Inc.       (804) 864-7470
Mail Stop 157-B                      (804) 864-7604 FAX
NASA Langley Research Center
Hampton, VA 23665

------------------------------------------------------------------------------
"I do not feel obliged to believe that the same God who endowed us with sense,
reason and intellect has intended us to forgo their use."   -- Galileo Galilei
------------------------------------------------------------------------------
Newsgroups: sci.misc
From: alex@bilver.uucp (Alex Matulich)
Subject: Re: Microwaves in a microwave oven?
Organization: W. J. Vermillion - Winter Park, FL
Date: Sat, 11 Apr 1992 20:00:56 GMT
Keywords: dielectrics, absorption


An excellent followup to my article!

ornitz@kodak.kodak.com (Barry Ornitz) writes:
>alex@bilver.uucp (Alex Matulich) writes:
>>When I was doing radar testing of materials at General Dynamics some years
>>back, we did transmission testing of water.  I can't say that the higher
>>attenuation we observed at approx. 2 GHz was a "resonant frequency" but it
>>was certainly an absorbtion frequency.
>
>You are on the right track, but I believe your memory is somewhat faulty.
>Water is a good absorber over an EXTREMELY broad frequency range.  In terms of

I know that, we characterized it from .5 GHz to 18 GHz.  Pretty flat
except around 2 GHz, which is why I said what I said.

It is possible that there was a fault with our measurement, because the 2
GHz range was at one end of two different testable bandwidths for us
(we needed different equipment above and below).

>You are correct about dielectric constants.  Von Hippel's various books on
>dielectrics give graphs of the complex permittivity of water as a function of
>frequency and temperature.  [Permittivity is the correct term - the dielectric

Ah, Von Hippel was our bible!  Every time we developed a new material
measurement system, or analytical method, we always checked against Von
Hippel's results.  Amazingly, we did find a few inaccuracies in his data
here and there.  Can't remember what they were offhand; this was 4 years
ago.

>more uniform heating.  Home ovens are far from uniform as you can easily
>demonstrate with a plate full or marshmellows!

Or a bowl of butter cubes!  Or a tray of raw cookies!  My mother once
accidentally burned some cookies in the microwave.  We turned all the
cookies over at once to reveal their undersides, and then looked at the
array of cookies.  Dark burn lines were visible, radiating outward from the
general center of the cookie array.  That's something that you wouldn't
expect from a conventional oven.

>To summarize - home microwave ovens operate at the frequency they do because
>of a number of factors: engineering, economics, dielectric properties, and
>politics - not because of any special resonant absorption phenomena.

Agreed.

-- 
 _ |__  Alex Matulich
 /(+__>  Unicorn Research Corp, 4621 N Landmark Dr, Orlando, FL 32817
//| \     UUCP:  alex@bilver.uucp   {peora|ge-dab|uunet!tous}!bilver!alex
///__)     Internet:  alex%bilver@peora.sdc.ccur.com
Newsgroups: sci.misc,sci.math,misc.wanted,misc.consumers,misc.education
From: reinhard@scivax.stsci.edu
Subject: A U.S. President and Pythagorean?
Organization: Space Telescope Science Institute
Distribution: na
Date: Thu, 9 Apr 1992 13:07:34 GMT


Can any one tell me which U.S. President developed
a proof to the Pythagorean Theorem?

Kent
From: toma@cdc910b21.gsfc.nasa.gov (Tom Atwater)
Newsgroups: sci.misc
Subject: Re: Understanding Dolphin talk
Date: 6 Apr 92 16:40:58 GMT
Article-I.D.: nsisrv.1992Apr6.164058.2357
Organization: NASA Goddard Space Flight Center, Greenbelt, MD
Originator: toma@cdc910b21.gsfc.nasa.gov

I need to set the record straight on this:

I wrote:
>>There is a guy named Lilley Or Lilly, first name Robert (I think), who has
>>spent his life doing this, and I believe has written books.
>>He is considered flaky by some -- e.g., he uses psychoactive drugs.

Small Systems Solutions wrote
>Do you know this for a fact, or are you just repeating what you've heard?
>If you can't get his name right, I don't trust your biography. 

"Tog" wrote:
>The people Atwater refers to are the sort who
>figure "Oh, Lilly's obviously been brain-damaged by LSD, or he wouldn't be
>trying to talk to dolphins..." which enables them to re-direct the question 
>from dolphin communication to drug abuse.

Paul Schmidt wrote:
>There was an article in Omni magazine about Lilly about ten years ago.  He
>did an interview and talked about some of the psychoactive drugs he did.
>He told how he almost died from one instance after a 200 day high.  They
>also talked about how the movie "Altered States" was based loosely on him.
>I think Tom may be generous by saying he is considered flaky by some, after
>reading the article.


Now: my only source of information about Lilly is the Omni article.
Given the nature of that (or any) magazine, I would not be at all surprised
to learn that the picture of him painted there was an exaggeration -- he
certainly came through as an eccentric. I mentioned it because the
original person who posted was asking for information leads; I
certainly did not intend it as a "biography".

I myself believe that (1) he probably has done some very important work
and (2) it is very possible that dolphins are in the same relationship
to the sea as we are to the land, namely the species that has chosen
to experience life by manipulating with its rational minds and
(3) wise use of psychoactive drugs can probably be very beneficial
(though I have had little experience with them myself).

You can call me flaky too - I don't mind!


-- 
Tom Atwater
From: hbg6@phx.mcd.mot.com (John Schuch)
Newsgroups: sci.misc
Subject: Re: TIME TRAVEL
Date: 6 Apr 92 21:34:52 GMT
Organization: Motorola Computer Group, Tempe, Az.

In article <VLaoiB3w164w@phsbbs.princeton.nj.us> arnold@phsbbs.princeton.nj.us (Jonathan Hefler) writes:
>Hi, I am looking to discuss theories of Time Travel and Quantum 
>Mechanics. I am not well versed in Quantum Mechanic lingo, but if anyone 
>would like to discuss Time Travel, please write to me. Thanx.

About time travel, don't do it.
I had a bad experience about two years from now, I won't be the same since.
Newsgroups: sci.misc
From: c60a-li@congo.Berkeley.EDU (John Hutton Cooper)
Subject: Re: TIME TRAVEL
Organization: University of California, at Berkeley
Date: Wed, 15 Apr 1992 02:51:27 GMT

In article <VLaoiB3w164w@phsbbs.princeton.nj.us> arnold@phsbbs.princeton.nj.us (Jonathan Hefler) writes:
>Hi, I am looking to discuss theories of Time Travel and Quantum 
>Mechanics. I am not well versed in Quantum Mechanic lingo, but if anyone 
>would like to discuss Time Travel, please write to me. Thanx.
>
>-----
>Jonathan Hefler, Princeton High School BBS
>DNS: arnold@phsbbs.princeton.nj.us      UUCP: ...!princeton!phsbbs!arnold
>Disclaimer: Author bears full responsibility for this message.

To: arnold@phsbbs.princeton.nj.us
Subject: Re: TIME TRAVEL
Newsgroups: sci.misc
Organization: University of California, at Berkeley
Cc: 
Bcc: 

I have no credentials as a scientist (for the time being) but I'll talk
about time travel.  Time travel into the future is pretty easy.  Just 
travel near the speed of light and the time going by on Earth is greater
than the time you experience, and so you can travel 10,000 years into
the future if you go fast enough.

Time travel into the past is more difficult.  Problems arise when you
try to change the past or know the future.  Suppose you're hanging
around some lab where the time of decay of an atom is measured.
The time it takes to decay is random; no one should be able to predict 
it.  Suppose it decays after 29 seconds.  Then, a month later
you climb into your time machine, go back in time, and see the same
demonstration.  You shouldn't be able to predict when that atom
decomposes.  Quantum mechanics is not deterministic.  What I imagine
would happen is that you the decay time wouldn't be exactly 29 seconds.
In other words, the universe takes a different branch, becoming an 
alternate universe, and everything would end up different.  The number
of things that happen one way or the other is incredibly large, so
the chance that you could get back home again goes to zero.

I think that's the only way time travel into the past can be consistent
with the laws of physics.
From: ornitz@kodak.kodak.com (Barry Ornitz)
Newsgroups: sci.misc
Subject: Re: Microwaves NOT in a microwave oven?
Summary: Seriously doubt it!
Keywords: microwave, hotdog, energy
Date: 7 Apr 92 22:33:54 GMT
Article-I.D.: kodak.1992Apr7.223354.17224
Followup-To: sci.misc
Organization: Eastman Kodak Company, Eastman Chemical Company Research Labs

In article <1992Apr6.212912.18723@phx.mcd.mot.com> hbg6@phx.mcd.mot.com 
(John Schuch) writes:
>I have a close friend who is an engineer at the local PBS TV affiliate.
>He has mentioned a few times that they can cook hot dogs by skewering
>them with a stick and holding them, one at a time, in front of the
>microwave transmitter dish on their remote van. He said it takes about
>5 minutes ( as opposed to one in an oven ) but works quite well. He is
>not known to exagerate ( or fib ) so I believe him.

Let's do a simple back-of-the-envelope calculation to see if this is possible.

Assume you have a small, run-of-the-mill hotdog and not a big, fat knockwurst.
I would guess this would be about eight per pound or two ounces each.  Assume
it has to be heated from 72 F to the boiling point of 212 F, a difference of
140 F.  I do not have any specific heat data for hotdogs but a reasonable
guess would be about half that of water.  Running this out, I calculate that
the heat needed is about 8.25 BTU.  To do this in five minutes, it takes about
105 BTU/hr of heat transfer.  Assuming all of the energy from the microwave is
available to heat the hotdog (which is NOT a reasonable assumption), this
corresponds to a power level of approximately 31 watts.

Most STL (studio to transmitter links) and similar remote microwave links
use a power level of less than 10 watts.  Considering the hotdog cannot absorb
all of the power coming from the dish (consider the area of the dish and the
area of the hotdog as a first approximation), it is VERY unlikely that this
story can be true.  If you stuffed the hotdog down the waveguide so the
energy transfer would be optimum and all of the microwave energy went into the
hotdog, the energy level is probably still too low.  Microwave ovens are
operated as multi-mode resonant cavities, of course, so all of the microwave
energy gets bounced around enough to be absorbed (a small amount gets back to
the magnetron as reflected power creating standing waves in the tube to oven
waveguide).

My conclusion is that this story is quite improbable!

				Barry L. Ornitz   ornitz@kodak.com
Xref: sparky sci.misc:1043 sci.math:5957 misc.wanted:4978 misc.consumers:10373 misc.education:1866
From: hrubin@pop.stat.purdue.edu (Herman Rubin)
Newsgroups: sci.misc,sci.math,misc.wanted,misc.consumers,misc.education
Subject: Re: A U.S. President and Pythagorean?
Date: 11 Apr 92 20:44:21 GMT
Followup-To: sci.misc
Distribution: na
Organization: Purdue University Statistics Department

In article <1992Apr9.153901.5109@newshost.lanl.gov> ttw@beta.lanl.gov (Tony Warnock) writes:

>   It was James A. Garfield. His proof was different from the
>   preceeding proofs. I do not remember in what manner. The
>   Pythagorean Theorem has hundreds of different proofs.

His proof is essentially using half of the figure of Bhaskara's (sp?) proof,
although it is quite possible he did not know that proof.  The figure is that
of a trapezoid with vertical left side, and right angles at the left corners.
If the triangle has sides a and b, and hypotenuse c, the figure has horizontal
lengths of a and b, vertical a+b, and one equates the area of the trapezoid
with the sum of two copies of the original triangle and an isosceles right
triangle with side c.
-- 
Herman Rubin, Dept. of Statistics, Purdue Univ., West Lafayette IN47907-1399
Phone: (317)494-6054
hrubin@pop.stat.purdue.edu (Internet, bitnet)  
{purdue,pur-ee}!pop.stat!hrubin(UUCP)
From: john_palkovic@ssc.gov
Newsgroups: sci.misc
Subject: Re: Microwaves NOT in a microwave oven?
Date: 6 Apr 92 07:44:37 GMT
	<1992Apr2.215650.11157@kodak.kodak.com>
Followup-To: sci.misc
Organization: Medium Energy Booster RF, SSCL

>I thought you knew better than this.  Microwave ovens do NOT
>operate on any resonant frequency of water.

Maybe, maybe not.

I recall an "Amateur Scientist" article by Jearl Walker in Sci. Am.
where he was claiming most of the absorption by water in a
microwave oven was due to a resonant mode which involved three H20
molecules coupled together. Sorry, I don't have the ref.

Adios,

-John
--
john_palkovic@ssc.gov
I joined the League for Programming Freedom -- send mail to john@phc.org
The SSC, the DOE, and the URA are not my mother.
Newsgroups: sci.misc
Subject: Solar Collection/Fresnel lenses
From: richard@ee.byu.edu (Richard Christensen)
Date: 8 Apr 92 13:54:38
Organization: Brigham Young University, Provo UT USA
Originator: richard@remus.ee.byu.edu


I want to do some experiments with solar collection.  The specs of
Edmund Scientific's fresnel lenses are surface area, focal length,
and lines per inch.  How does one figure which lens would
give the highest power density (W/m^2)  (hottest spot).  I used
this formula Area / (Pi (f A)^2).  This gives a relative power density
into a lens with the power desity of the focused image.
Does this make sense?
Edmund Scientific told me that the only thing that mattered was
the number of lines per inch.  The lower the better (counter-intuitive
isn't it).  Given that the lines per inch are equal, the power
densities will be equal.  I have a hard time believing this?

Any help would be appreciated.

--
-------------------------------------------------------
| Richard B. Christensen                              |
| richard.ee.byu.edu                                  |
| Brigham Young University 459 CB Provo, Utah 84602   |
-------------------------------------------------------
--
-------------------------------------------------------
| Richard B. Christensen                              |
| richard.ee.byu.edu                                  |
| Brigham Young University 459 CB Provo, Utah 84602   |
Newsgroups: sci.misc,sci.math,misc.wanted,misc.consumers,misc.education
From: edgar@function.mps.ohio-state.edu (Gerald Edgar)
Subject: Re: A U.S. President and Pythagorean?
Organization: The Ohio State University, Dept. of Math.
Distribution: na
Date: Thu, 9 Apr 1992 15:30:25 GMT


Garfield found a proof of the Pythagorean Theorem.  Of course, this was
before he was President.  The story says that he found the proof
when he was a member of the House of Representatives,
while doodling one day during a boring speech...

The proof, known in the literature of the Pythagorean theorem as
"General Garfield's Demonstration", was reprinted in the Mathematical
Magazine, volume I, no. 1, page 7 (January 1882).

It was published originally in a magazine article, in 1876 or 1877,
but that reference is apparently unknown:  a copy of it was pasted
in the flyleaf of somebody's old geometry book, and so Garfield's
proof is known today only because of that copy.

--
  Gerald A. Edgar                Internet:  edgar@mps.ohio-state.edu
  Department of Mathematics      Bitnet:    EDGAR@OHSTPY
  The Ohio State University      telephone: 614-292-0395 (Office)
  Columbus, OH 43210             -292-4975 (Math. Dept.) -292-1479 (Dept. Fax)
From: tolman%asylum.utah.edu@cs.utah.edu (Kenneth Tolman)
Newsgroups: sci.misc
Subject: Technology
Date: 7 Apr 92 16:21:11 GMT
Article-I.D.: hellgate.1992Apr7.102111.11710
Organization: University of Utah CS Dept


  Is there a newsgroup to discuss technological advance?  Does anyone know
of one?  If there is not one, then I am going to poke around for interest
here.


  Technological device for the week:  Smart structures.

In particular, it is possible now to have support structures with self
knowledge.  Fiber optic cables run through the structure in regular
intervals, like a nervous system.  Laser light is shown through these, and
any sort of bend (or fracture) can be detected because of attenuation.
Thus, the structure can tell when it is getting weak, about to break, or
under stress.  Now only if it could fix itself....


What possible applications does this have?
Newsgroups: sci.chem