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Re: Ballistic Theory and the Sagnac Experiment

Subject: Re: Ballistic Theory and the Sagnac Experiment
From: ""
Date: 7 Mar 2006 15:28:39 -0800
Newsgroups: sci.astro, sci.physics.relativity, sci.physics
George Dishman wrote:
> jgreenfield@xxxxxxxxxxx wrote:
> > George Dishman wrote:
> > > Excellent work Jeff. Hopefully Jim and Henry can
> > > see that the representations are valid. Since we
> > > are discussing Doppler shift I'll trim to the
> > > relevant part.
> > >
> > > "Jeff Root" <jeff5@xxxxxxxxxxxx> wrote in message
> > > news:1141648420.084849.280960@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
> > > >
> > > > I made a GIF animation to illustrate how the Doppler
> > > > effect works, comparing the four cases described by Jim
> > > > and Henry, in which a gunner shoots at a target and:
> > > >
> > > > 1) remains fixed
> > > > 2) advances as he fires but always fires from same place
> > > > 3) advances between shots
> > > > 4) advances at constant speed as he fires
> > > >
> > > > http://www.freemars.org/jeff2/Doppler.htm
> > > >
> > > ...
> > > >
> > > > When the first bullet from each gun hits the target, a
> > > > timer is started (red) which counts frames.  The timer
> > > > stops when the second bullet hits, and the elapsed time
> > > > between bullet hits is shown in green.  The times are:
> > > >
> > > > 1) 15.0 frames
> > > > 2) 15.0 frames
> > > > 3)  7.5 frames
> > > > 4) 10.0 frames
> > > >
> > > > Frequency of bullet strikes is the reciprocal of these
> > > > times, so cases 1 and 2 have the lowest frequency, while
> > > > case 3 has the highest frequency.
> > > ...
> > > > Jim Greenfield wrote on February 22, 2006:
> > > >
> > > ...
> > > >> (This clearly demonstrates that it is the MOTION of
> > > >> the gun at instant of firing which causes increased
> > > >> frequency/bullet velocity at target)
> > > >
> > > > That is case 3.
> > >
> > > Comparing (1) and (3), the motion of the gun at
> > > the time of firing is the same, both are at rest
> > > yet the hit frequency in (3) is double that of
> > > (1).

George, you are losing it!
(2) is an absolute red-herring until you introduce ENERGY compared to
the others.
The source has MASS, and the energies involved in toing and froing are
completely at odds with that of stationary or maintained velocity.
When we observe a doppler effect, do you _really_ believe that the
source is stopping at the instant (and for the purpose of) emitting a
photon? That would make for a helluva jerky ride!
The correct scenario is that comparing (1) and (4), because it accounts
for BOTH the noted doppler change in frequency, AND the energy increase
in (bullets / penetration) and light (bluer / more energetic)
> > >
> > > > Henri Wilson wrote on February 24, 2006:
> > > >
> > > >> The detected frequency is the rate at which wavecrests
> > > >> reach the target. That is dependent on the wave speed
> > > >> relative to the target.
> > >
> > > Comparing (1) and (2), this time the firing
> > > location is the same every time. The speed of the
> > > bullets is higher in (2) than in (1) yet the hit
> > > frequency in (2) is exactly the same as in (1).

> > >
> > > The diagram shows that, when only the speed of
> > > the bullets changes, there is NO effect on the
> > > hit rate at the target (even though Henry the
> > > wavelength IS changed) and when the firing
> > > location varies, there IS a change of frequency
> > > even if the speed is unchanged.
> > >
> > > Nice one Jeff, thank you for injecting some common
> > > sense into the proceedings.
> > >
> > > George
> >
> > Luckily I didn't have a mouthfull of beer when I read this last; it
> > would be all over the
> > computer!!!!!!!!!
>
> Sober up and try again.
>
> > FYI: "moving forward" and "firing fromthe same position" are
> > OXYMORONIC.
>
>  http://www.freemars.org/jeff2/Doppler1.gif
>
> Can you see that rifleman (2) is both "moving
> forward when firing" and "firing from the same
> position" each time?
>
> > I presume Jeff is referring to your carousel,
>
> No, he's referring to the diagram at the top of
> his page. I guess he assumed you would look
> at it before trying to comment on it:
>
>  http://www.freemars.org/jeff2/Doppler.htm
>
> Comparing (1) and (3), the speed of the bullets is
> the same but the hit rates differ. Comparing (1)
> and (2), the speed of the bullets is higher in (2)
> yet the hit rates are identical. Your belief that
> higher speed causes the change of hit rate is
> therefore shown to be incorrect.
>
> George

Laws of conservation of energy to which I subscribe
show observed doppler due to (1) / (4)
(Also ridicules moving masses and FoRs)
Your silence on the issue betrays your position.

Jim G
c'=c+v


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