Re: OT Speed of light stuff


"Kevin W. Miller" <i09172strudelyahoo.com> wrote in message
news:UPydnerqTMfjmUTenZ2dnUVZ_v2dnZ2d@xxxxxxxxxxxxxxx
> In news:43s5k9F1okahoU1@xxxxxxxxxxxxxx,
> Cliff <cliffclingan@xxxxxxxxxxx> typed:
>> Max wrote:
>>> Some of the posts on this subject are giving some of us a good
>>> insight to the reasoning of the posters.
>>> I'm beginning to see whose logic I can trust.
>>>
>>> Max
>>
>> Speaking of that, has anyone on here ever wondered just *What* kind
>> of time piece the scientist used to measure the speed of that
>> experiment? Certainly not a Timex stop-watch!!! And just how *Do*
>> you measure something 300 times the speed of light? And *How* do
>> they know it has arrived, if they haven't sent it yet??? How do you
>> measure the speed of light, for that matter? Inquiring minds
>> ..... Cliff in FL
>
> Which experiment?
>
> Kevin W. Miller
>

This headache producing thread has caused me to think about something
related, and maybe can shed some "light" on Cliff's question of how to you
measure this stuff.

There's a device developed in the past 15 years or so called a "Ring Laser
Gyro" (RLG). Very simply put, here's how it works and what it does:

First, it's important to understand that a laser, unlike a regular light
source, is polarized, meaning it's wavefronts all rise and fall in a line.
Regular light has wavefronts going all over the place. Okay.

Picture a perfect triangle. Within the boundary lines of the triangle,
place three mirrors at each corner where the lines of the triangle meet. The
mirrors are perfectly aligned kitty-corner in each corner of the triangle.

One of these mirrors is not a complete mirror. It is a beam splitter that
transmits half of the light and reflects half of the light. At the
beamsplitter location a laser beam is introduced that travels parallel to
the lines of the triangle, reflecting off and being redirected by each
mirror to follow the triangle. When the beam reaches the beam splitter
mirror, some of it's energy is allowed to pass through and hit a laser
detector.

Now picture that instead of one beam being introduced and bouncing from
mirror to mirror, *two* beams are simultaneously introduced except one
travels clockwise and the other travels counter-clockwise around the mirror
path. This device is so precise, and path distances are so perfectly
identical that the two laser beams stay perfectly in phase with relation to
each other as represented by the output of the detectors.

With the beams running, start to rotate the entire device clockwise. The
movement will cause the clockwise beam path to become longer and the
counter-clockwise path to become shorter, in terms of how long it takes each
beam to travel it's path. The result of this movement will cause the laser
beams to become out of phase on the detectors which can easily be read with
instrumentation. (you don't have to use a super dooper stopwatch).

When the rotation of the RLG stops, the path lengths appear equal again and
the beams are back in phase. The faster you rotate the RLG, the more out of
phase the beams become.

This device is relative to nothing on earth or space except it's own
dimensions. Even the speed of the laser beam could vary and it would still
work, as long as both beams originate from the same laser.

BTW - this device now navigates just about all major commercial aircraft
types. Three or more measure roll, yaw and pitch. The design has changed
(I think they now use fiber optics instead of mirrors) but it replaces the
old, earth relative gyroscopes.

Eisboch (more useless information)


.

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