Fwd: Re: [asa] writing equations - a request

Merv inadvertently sent this directly to me instead of the list and asked me to
forward it. Maybe I'm too practical (a characteristic of engineers) but it
seems to me that energy must be dissipate4d by the clothes being ironed,
otherwise there is no 0point in ironi8ng them. Dissipated energy is not
recoverable.

--- mrb22667@kansas.net wrote:

> Date: Fri, 21 Jul 2006 09:32:38 -0500
> From: mrb22667@kansas.net
> To: Bill Hamilton <williamehamiltonjr@yahoo.com>
> Subject: Re: [asa] writing equations - a request
>
> But if the perfectly reflective enclosure is complete wouldn't any "non-point
> source" radiation just bounce around in there until it came back to one of
> the
> irons? Regarding the re-radiation at a lower temp. -- expand on the
> consequences of that if you would. So if the radiation wavelength becomes
> longer (for a lower temp.) would it become more intense? How does energy
> conservation come into play in this? We continue to assume everything is
> idealized of course.
>
> --merv
>
> Quoting Bill Hamilton <williamehamiltonjr@yahoo.com>:
>
> > The clothes and the ironing board are not point sources, so their
> > reradiation
> > is not reflected back to the other focus. + as others have said the
> > reradiation
> > is at a lower temperature.
> >
> > --- George Murphy <gmurphy@raex.com> wrote:
> >
> > > Sure, but the clothes & the ironing borad then re-radiate energy.
> > >
> > > Shalom
> > > George
> > > http://web.raex.com/~gmurphy/
> > > ----- Original Message -----
> > > From: "Bill Hamilton" <williamehamiltonjr@yahoo.com>
> > > To: "George Murphy" <gmurphy@raex.com>; "ASA list" <asa@calvin.edu>;
> > "Janice
> > > Matchett" <janmatch@earthlink.net>
> > > Sent: Thursday, July 20, 2006 8:30 PM
> > > Subject: Re: [asa] writing equations - a request
> > >
> > >
> > > >I _still_ say that energy from the irons is absorbed by the clothes
> being
> > > > ironed and therefore not available for heating thee other iron. In
> > > > addition,
> > > > the iron must rest on an ironing board, which would prevent some of the
> > > > radiation from reaching the ellipsoid.
> > > >
> > > > --- George Murphy <gmurphy@raex.com> wrote:
> > > >
> > > >> With perfect reflectors &c - again this is an ideal Gedankenexperiment
> -
> >
> > > >> all
> > > >> the rays emitted by the iron should go to the other focus.
> > > >>
> > > >> But ray optics is only an approximation.
> > > >>
> > > >> Shalom
> > > >> George
> > > >> http://web.raex.com/~gmurphy/
> > > >> ----- Original Message -----
> > > >> From: "Bill Hamilton" <williamehamiltonjr@yahoo.com>
> > > >> To: "George Murphy" <gmurphy@raex.com>; "ASA list" <asa@calvin.edu>;
> > > >> "Janice
> > > >> Matchett" <janmatch@earthlink.net>
> > > >> Sent: Thursday, July 20, 2006 3:09 PM
> > > >> Subject: Re: [asa] writing equations - a request
> > > >>
> > > >>
> > > >> > What about
> > > >> > the heat energy that is disipated from the iron into the clothes
> > > >> > the heat energy that is absorbed by the air between the two irons
> > > >> > the heat energy that is absorbed by objects in the room
> (including
> >
> > > >> > the
> > > >> > person doing the ironing)
> > > >> > ???
> > > >> >
> > > >> > --- George Murphy <gmurphy@raex.com> wrote:
> > > >> >
> > > >> >> Sort of, but the connection is pretty remote.
> > > >> >>
> > > >> >> The thrifty owners of the laundry have constructed their building
> in
> >
> > > >> >> the
> > > >> >> form
> > > >> >> of an ellipsoid, and put irons at both foci. All the radiation
> from
> >
> > > >> >> an
> > > >> >> instrument at one focus as it irons clothes is reflected to the
> > other
> > > >> >> focus
> > > >> >> (by a well known property of the ellipse) & heats the other iron,
> > > >> >> which
> > > >> >> can
> > > >> >> then be used to iron other clothes. No heat is lost & no money
> needs
> >
> > > >> >> to
> > > >> >> be
> > > >> >> spent in heating the irons once they've been heated up initially.
> > > >> >>
> > > >> >> What's wrong with this picture?
> > > >> >>
> > > >> >> (Of course an iron - whether a "mangle" or the usual household
> > > >> >> variety -
> > > >> >> isn't a mathematical point but that's not the "point" here.)
> > > >> >>
> > > >> >> Shalom
> > > >> >> George
> > > >> >> http://web.raex.com/~gmurphy/
> > > >> >> ----- Original Message -----
> > > >> >> From: Janice Matchett
> > > >> >> To: George Murphy ; ASA list
> > > >> >> Sent: Thursday, July 20, 2006 12:17 PM
> > > >> >> Subject: Re: [asa] writing equations - a request
> > > >> >>
> > > >> >>
> > > >> >> At 11:27 AM 7/20/2006, George Murphy wrote:
> > > >> >>
> > > >> >>
> > > >> >> A teaser: How many know "The paradox of the Chinese laundry"?
> > > >> >>
> > > >> >>
> > > >> >> @ Physicists know that we don't live in a frictionless world, so
>
> > > >> >> does
> > > >> >> it
> > > >> >> have anything to do with a lack of friction?
> > > >> >>
> > > >> >> ~ Janice
> > > >> >>
> > > >> >>
> > > >> >>
> > > >> >>
> > > >> >
> > > >> >
> > > >> > Bill Hamilton
> > > >> > William E. Hamilton, Jr., Ph.D.
> > > >> > 248.652.4148 (home) 248.821.8156 (mobile)
> > > >> > "...If God is for us, who is against us?" Rom 8:31
> > > >> >
> > > >> > __________________________________________________
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> > > >>
> > > >>
> > > >> To unsubscribe, send a message to majordomo@calvin.edu with
> > > >> "unsubscribe asa" (no quotes) as the body of the message.
> > > >>
> > > >
> > > >
> > > > Bill Hamilton
> > > > William E. Hamilton, Jr., Ph.D.
> > > > 248.652.4148 (home) 248.821.8156 (mobile)
> > > > "...If God is for us, who is against us?" Rom 8:31
> > > >
> > > > __________________________________________________
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> > > >
> > >
> > >
> >
> >
> > Bill Hamilton
> > William E. Hamilton, Jr., Ph.D.
> > 248.652.4148 (home) 248.821.8156 (mobile)
> > "...If God is for us, who is against us?" Rom 8:31
> >
> > __________________________________________________
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> >
>
>
>

Bill Hamilton
William E. Hamilton, Jr., Ph.D.
248.652.4148 (home) 248.821.8156 (mobile)
"...If God is for us, who is against us?" Rom 8:31

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Received on Fri Jul 21 16:02:16 2006