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Topic: nasa.gov/scientific-consensus
Replies: 111   Last Post: Jun 18, 2014 1:15 PM

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Michael J. Strickland

Posts: 20
Registered: 5/22/14
Re: nasa.gov/scientific-consensus
Posted: May 30, 2014 6:37 AM
  Click to see the message monospaced in plain text Plain Text   Click to reply to this topic Reply

"Greg Goss" <gossg@gossg.org> wrote in message
news:buqcijF4m7fU1@mid.individual.net
> "Michael J. Strickland" <michael0658@comcast.net> wrote:
>

> > "Greg Goss" <gossg@gossg.org> wrote
>
> > > I love conspiracy theories, though I'm rational enough to set them
> > > aside when I'm done with them.
> > >
> > > My favourite at the moment is that "chemtrails" is a project to
> > > disperse high altitude sulfates to cancel out some global warming.
> > > After all, we started departing from the model predictions about
> > > 2000.

>
> > I'm not so sure because the soot would probably just have absorbed
> > incoming and outgoing heat and shed it to the rest of the air.

>
> > When something is perfectly reflected (like light into a mirror), it
> > delivers twice the momentum (and 4 times the energy, E = p^2/2m) as
> > when it is absorbed. Any attempt to "screen" out radiation with air
> > chemicals will just double the energy deposited in the air after
> > the reflector molecules are accelerated and shed their energy to
> > neighboring molecules. Absorbing chemicals will only add half as
> > much energy to the air.
> >
> > How is this "chemtrail" cancelation supposed to work. If its trying
> > to increase screening, I don't have much hope for it. If its trying
> > to react the chemicals with existing greenhouse molecules to
> > precipitate them out, it might work.

>
> Soot and sulfate work differently. Soot absorbs the energy and
> re-radiates it. ("black body")


With loss, or else the soot would not heat up.

> Sulfate reflects it. When something is perfectly reflected it absorbs
> double the energy? Momentum maybe, but the energy departs back into
> space. Energy is a scalar amount, not a vector.


No, an amount of energy equal to twice the incoming energy of the photon
is deposited in the reflector as recoil kinetic energy.

The total energy of the system (photon and reflector molecule) must
remain the same before and after reflection since no external energy is
added.

The initial energy of the incoming photon is E_i = pc.

After reflection, the photon's energy is E_f = -pc since its momentum (p
= hf/c) has been reversed (c -> -c).

In order for system energy to be conserved, the reflector must acquire
an energy E_r = 2pc.

E_i = E_p + E_r
or
pc = -pc + 2pc

This balances the energy equation.

Therefore, the reflector molecule must acquire energy, E_r = 2pc.

This energy shows up as recoil energy for an isolated atom. For a
lattice of bound atoms it shows up as macroscopic kinetic energy because
the lattice atoms are bound to their neighboring atoms by much stronger
forces than the incoming photon delivers.

Alternative explanation:
You could say the photon is red-shifted to a lower frequency (and
energy) upon reflection due to the Doppler imparted by the reflector
which starts moving away in the opposite direction. This seems kind of
non-causal to me though, since the reflector is originally stationary
when the photon hits it.

This is how a solar sail accelerates (gains kinetic energy).

Think about it. How can the reflector acquire linear momentum (mv)
without acquiring translational kinetic energy (1/2 mv^2)? It can't. If
v increases, both energy and momentum increase.

Btw, I believe maybe energy should be expressed as vector, but that's
another story.


> If you shine a bathroom heat lamp onto a mirror, are you saying that
> the back of the mirror gets HOTTER than the guy standing next to the
> heat lamp?


Heat is random direction energy (e.g. vibration). A solar sail acquires
energy but little heat (random motion) because its molecules are tightly
bound in a lattice so they can't move independently of the atoms they
are bound to like a liquid or gas molecule. The energy is given to the
crystal lattice as a whole, so the whole lattice experiences a force
away from the light source. Not so for individual gaseous reflector
molecules. They are not tightly coupled in a lattice and absorb the
energy individually when they "reflect". They recoil and transfer energy
to neighboring atoms which shows up as heat (random motion).

For the heat lamp, the mirror gains energy and is in fact pressed
against the wall and both heat up some due to their electrons clouds
being pushed together. Again, since its solid, its electrons and atoms
are tightly bound in a lattice by much stronger forces than the incoming
EM and so incoming light tends to move the entire lattice of the mirror
away from the light.

The guy standing next to the heat lamp is a better absorber than the
mirror molecules. His water molecules are more mobile (unbound) and
absorb (vibrate)well in infra-red which he feels as heat.


--
------------------------------------------------------------

Michael J. Strickland Reston, VA
michael0658@comcast.net
------------------------------------------------------------





Date Subject Author
5/27/14
Read nasa.gov/scientific-consensus
The Starmaker
5/27/14
Read Re: nasa.gov/scientific-consensus
Peter Percival
5/27/14
Read Re: nasa.gov/scientific-consensus
Thomas Heger
5/27/14
Read Re: nasa.gov/scientific-consensus
The Starmaker
5/28/14
Read Re: nasa.gov/scientific-consensus
The Starmaker
5/28/14
Read Re: nasa.gov/scientific-consensus
Thomas Heger
5/28/14
Read Re: nasa.gov/scientific-consensus
Mike
5/28/14
Read Re: nasa.gov/scientific-consensus
William December Starr
5/28/14
Read Re: nasa.gov/scientific-consensus
The Starmaker
5/29/14
Read Re: nasa.gov/scientific-consensus
Michael J. Strickland
5/29/14
Read Re: nasa.gov/scientific-consensus
The Starmaker
5/28/14
Read Re: nasa.gov/scientific-consensus
Greg Goss
5/28/14
Read Re: nasa.gov/scientific-consensus
Don Kuenz
5/29/14
Read Re: nasa.gov/scientific-consensus
Michael J. Strickland
5/29/14
Read Re: nasa.gov/scientific-consensus
Greg Goss
5/30/14
Read Re: nasa.gov/scientific-consensus
Michael J. Strickland
5/28/14
Read Re: nasa.gov/scientific-consensus
The Starmaker
5/29/14
Read Re: nasa.gov/scientific-consensus
The Starmaker
5/29/14
Read Re: nasa.gov/scientific-consensus
The Starmaker
5/29/14
Read Re: nasa.gov/scientific-consensus
Kirby Grant
5/29/14
Read Re: nasa.gov/scientific-consensus
kefischer
5/30/14
Read Re: nasa.gov/scientific-consensus
J. Clarke
5/30/14
Read Re: nasa.gov/scientific-consensus
Cryptoengineer
5/30/14
Read Re: nasa.gov/scientific-consensus
The Starmaker
5/30/14
Read Re: nasa.gov/scientific-consensus
kefischer
5/31/14
Read Re: nasa.gov/scientific-consensus
William December Starr
5/29/14
Read Re: nasa.gov/scientific-consensus
Michael J. Strickland
5/29/14
Read Re: nasa.gov/scientific-consensus
kefischer
5/29/14
Read Re: nasa.gov/scientific-consensus
antani
5/29/14
Read Re: nasa.gov/scientific-consensus
kefischer
5/29/14
Read Re: nasa.gov/scientific-consensus
R Kym Horsell
5/29/14
Read Re: nasa.gov/scientific-consensus
Thomas Heger
5/30/14
Read Re: nasa.gov/scientific-consensus
J. Clarke
5/31/14
Read Re: nasa.gov/scientific-consensus
Thomas Heger
5/31/14
Read Re: nasa.gov/scientific-consensus
J. Clarke
6/1/14
Read Re: nasa.gov/scientific-consensus
Thomas Heger
5/31/14
Read Re: nasa.gov/scientific-consensus
cloud dreamer
6/2/14
Read Re: nasa.gov/scientific-consensus
Jim G.
6/2/14
Read Re: nasa.gov/scientific-consensus
kefischer
6/2/14
Read Re: nasa.gov/scientific-consensus
cloud dreamer
6/2/14
Read Re: nasa.gov/scientific-consensus
2ju
6/2/14
Read Re: nasa.gov/scientific-consensus
kefischer
6/2/14
Read Re: nasa.gov/scientific-consensus
Greg Goss
6/2/14
Read Re: nasa.gov/scientific-consensus
Greg Goss
6/2/14
Read Re: nasa.gov/scientific-consensus
Lynn McGuire
6/3/14
Read Re: nasa.gov/scientific-consensus
Greg Goss
6/3/14
Read Re: nasa.gov/scientific-consensus
kefischer
6/3/14
Read Re: nasa.gov/scientific-consensus
Greg Goss
6/3/14
Read Re: nasa.gov/scientific-consensus
kefischer
6/3/14
Read Re: nasa.gov/scientific-consensus
Jim G.
6/2/14
Read Re: nasa.gov/scientific-consensus
William December Starr
6/3/14
Read Re: nasa.gov/scientific-consensus
kefischer
5/31/14
Read Re: nasa.gov/scientific-consensus
R Kym Horsell
5/31/14
Read Re: nasa.gov/scientific-consensus
J. Clarke
6/3/14
Read Re: nasa.gov/scientific-consensus
Bill Steele
6/3/14
Read Re: nasa.gov/scientific-consensus
R Kym Horsell
6/3/14
Read Re: nasa.gov/scientific-consensus
kefischer
6/3/14
Read Re: nasa.gov/scientific-consensus
J. Clarke
6/3/14
Read Re: nasa.gov/scientific-consensus
Virgil
6/3/14
Read Re: nasa.gov/scientific-consensus
kefischer
6/3/14
Read Re: nasa.gov/scientific-consensus
Peter Trei
6/4/14
Read Re: nasa.gov/scientific-consensus
Virgil
6/4/14
Read Re: nasa.gov/scientific-consensus
kefischer
6/4/14
Read Re: nasa.gov/scientific-consensus
J. Clarke
6/4/14
Read Re: nasa.gov/scientific-consensus
The Starmaker
6/4/14
Read Re: nasa.gov/scientific-consensus
Lynn McGuire
6/4/14
Read Re: nasa.gov/scientific-consensus
R Kym Horsell
6/4/14
Read Re: nasa.gov/scientific-consensus
J. Clarke
6/4/14
Read Re: nasa.gov/scientific-consensus
J. Clarke
6/5/14
Read Re: nasa.gov/scientific-consensus
Lynn McGuire
6/5/14
Read Re: nasa.gov/scientific-consensus
David Hartley
6/5/14
Read Re: nasa.gov/scientific-consensus
Greg Goss
6/5/14
Read Re: nasa.gov/scientific-consensus
The Starmaker
6/5/14
Read Re: nasa.gov/scientific-consensus
J. Clarke
6/5/14
Read Re: nasa.gov/scientific-consensus
Cryptoengineer
6/7/14
Read Re: nasa.gov/scientific-consensus
The Starmaker
6/8/14
Read Re: nasa.gov/scientific-consensus
Thomas Heger
6/8/14
Read Re: nasa.gov/scientific-consensus
The Starmaker
6/8/14
Read Re: nasa.gov/scientific-consensus
Thomas Heger
6/9/14
Read Re: nasa.gov/scientific-consensus
Peter Trei
6/10/14
Read Re: nasa.gov/scientific-consensus
The Starmaker
6/13/14
Read Re: nasa.gov/scientific-consensus
The Starmaker
6/17/14
Read Re: nasa.gov/scientific-consensus
The Starmaker
6/18/14
Read Re: nasa.gov/scientific-consensus
The Starmaker
6/7/14
Read Re: nasa.gov/scientific-consensus
The Starmaker
6/5/14
Read Re: nasa.gov/scientific-consensus
kefischer
6/5/14
Read Re: nasa.gov/scientific-consensus
The Starmaker
6/7/14
Read Re: nasa.gov/scientific-consensus
John F. Eldredge
6/4/14
Read Re: nasa.gov/scientific-consensus
kefischer
6/5/14
Read Re: nasa.gov/scientific-consensus
Thomas Heger
6/5/14
Read Re: nasa.gov/scientific-consensus
kefischer
6/5/14
Read Re: nasa.gov/scientific-consensus
The Starmaker
6/6/14
Read Re: nasa.gov/scientific-consensus
Thomas Heger
6/5/14
Read Re: nasa.gov/scientific-consensus
The Starmaker
6/5/14
Read Re: nasa.gov/scientific-consensus
Bill Steele
6/5/14
Read Re: nasa.gov/scientific-consensus
Thomas Heger
6/4/14
Read Re: nasa.gov/scientific-consensus
J. Clarke
6/4/14
Read Re: nasa.gov/scientific-consensus
kefischer
6/3/14
Read Re: nasa.gov/scientific-consensus
kefischer
5/30/14
Read Re: nasa.gov/scientific-consensus
cloud dreamer
5/30/14
Read Re: nasa.gov/scientific-consensus
kefischer
5/30/14
Read Re: nasa.gov/scientific-consensus
The Starmaker
5/30/14
Read Re: nasa.gov/scientific-consensus
cloud dreamer
5/30/14
Read Re: nasa.gov/scientific-consensus
kefischer
5/28/14
Read Re: nasa.gov/scientific-consensus
Michael J. Strickland
5/28/14
Read Re: nasa.gov/scientific-consensus
J. Clarke
5/28/14
Read Re: nasa.gov/scientific-consensus
William December Starr
5/29/14
Read Re: nasa.gov/scientific-consensus
Peter Trei
5/30/14
Read Re: nasa.gov/scientific-consensus
Michael J. Strickland
5/30/14
Read Re: nasa.gov/scientific-consensus
J. Clarke

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