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Cecil Moore June 30th 05 05:22 PM

Cecil Moore wrote:
Itot = I1 + I2 + Sqrt(I1*I2)cos(theta)


Sorry, should be:
Itot = I1 + I2 +2*SQRT(I1*I2)cos(theta)

Ptot = P1 + P2 + Sqrt(P1*P2)cos(theta)


Sorry should be:
Ptot = P1 + P2 + 2*Sqrt(P1*P2)cos(theta)
--
73, Cecil, http://www.qsl.net/w5dxp

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Richard Clark June 30th 05 06:41 PM

On Thu, 30 Jun 2005 11:18:37 -0500, Cecil Moore
wrote:
Sorry, I made a mistake in the equation.

....
Hows about reading it so I won't have to explain superposition to you?

Certainly no one stands any chance of understanding your explanations
given the continuing goof-ups.

Richard Clark June 30th 05 06:53 PM

On Thu, 30 Jun 2005 11:18:37 -0500, Cecil Moore
wrote:
When you superpose two 100w coherent laser beams, the resultant
power is indeed 400w

Yowza! You, with W's help, can roll your Social Security over into
investments in the CB amplifier Market.
and must be supplied by the sources

[Hecht rolling his eyes] So, this means that Hecht's formula only
works for steady state? :-)
If both are 100W pulses, and the lasers are off before the target are
pulse illuminated -um-
1.) 100W
2.) 200W
3.) 400W
4.) no hundred W
or supplied by destructive interference from somewhere else.

Maybe two more magic lasers?
This is all explained in _Optics_, by Hecht.

Somehow, I don't think so.

How many errors can our readers count?
For N = number of words in orginal posting
errors = N!

Such is the problem of Xerox research.

Richard Clark June 30th 05 07:04 PM

On Thu, 30 Jun 2005 12:08:05 -0400, "Fred W4JLE"
wrote:
SWR=Strewn With Rumor

SWR = Strife Without Regret

Cecil Moore June 30th 05 07:08 PM

Richard Clark wrote:
Certainly no one stands any chance of understanding your explanations
given the continuing goof-ups.


Richard, I cannot recall you and I ever disagreeing upon
a technical subject. Your objections are just personal
pot shots.
--
73, Cecil, http://www.qsl.net/w5dxp

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Richard Clark June 30th 05 07:11 PM

On Thu, 30 Jun 2005 13:08:52 -0500, Cecil Moore
wrote:
Richard, I cannot recall you and I ever disagreeing upon
a technical subject.

Convenient memory.

[email protected] June 30th 05 07:24 PM

When you superpose two 100w coherent laser beams, the resultant
power is indeed 400w


This is correct if the two beams are coherent and have the
same polarization. Very hard to do at optical frequencies, much
easier at lower frequencies.

Tor
N4OGW

Cecil Moore June 30th 05 07:28 PM

Richard Clark wrote:

Cecil Moore wrote:
When you superpose two 100w coherent laser beams, the resultant
power is indeed 400w


Yowza! You, with W's help, can roll your Social Security over into
investments in the CB amplifier Market.


Note the
following extremely important qualification. The extra power
must come from somewhere, either from the two sources or from
destructive interference. So says Hecht.

When you phasor add 100v to 100v, what V^2/Z0 do you get?

and must be supplied by the sources or or supplied by
destructive interference from somewhere else.


[Hecht rolling his eyes] So, this means that Hecht's formula only
works for steady state? :-)


Yep, irradiance is a quantity averaged over time. It is
steady-state by definition, an accumulated effect.

If both are 100W pulses, and the lasers are off before the target are
pulse illuminated -um-
1.) 100W
2.) 200W
3.) 400W
4.) no hundred W


You will get interference rings of 400w/unit-area and
rings of 0w/unit-area all averaging out to 200w total.
All this is covered in _Optics_. Please spare us your
ignorance and read the book.

If the sources are incapable of supplying the extra power,
For every P1+P2+2*SQRT(P1*P2), i.e. constructive interference,
there is a P1+P2-2*SQRT(P1*P2), i.e. destructive interference.
--
73, Cecil, http://www.qsl.net/w5dxp

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K7ITM June 30th 05 07:39 PM

Earlier today, I wrote, "...HP8653..." Ooops. Belay that. It's
HP8753E.


Richard Clark June 30th 05 07:41 PM

On Thu, 30 Jun 2005 13:28:24 -0500, Cecil Moore
wrote:
You will get interference rings

[Hecht rolling his eyes] for a target that is smaller than a
wavelength?
Must be another failure of Hecht (or Hecht pupil).
of 400w/unit-area and
rings of 0w/unit-area all averaging out to 200w total.

Which, of course, cannot be found in the formula:
Itot = I1 + I2 + 2*Sqrt(I1*I2)cos(theta)
nor its correction:
Itot = I1 + I2 +2*SQRT(I1*I2)cos(theta)
If the sources are incapable of supplying the extra power,

Which, in the end was a non sequitur.
For every P1+P2+2*SQRT(P1*P2), i.e. constructive interference,

Which, of course, cannot be found in the formula:
Itot = I1 + I2 + 2*Sqrt(I1*I2)cos(theta)
nor its correction:
Itot = I1 + I2 +2*SQRT(I1*I2)cos(theta)
there is a P1+P2-2*SQRT(P1*P2), i.e. destructive interference.

Which, of course, cannot be found in the formula:
Itot = I1 + I2 + 2*Sqrt(I1*I2)cos(theta)
nor its correction:
Itot = I1 + I2 +2*SQRT(I1*I2)cos(theta)

When combined with the adhominem (which, of course, reveals another
inaccuracy, one of assignment):
Please spare us your ignorance and read the book.

is possibly the best advice (once the assignment is corrected), given
the continuing goof-ups.


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