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Re: Ballistic Theory and the Sagnac Experiment

Subject: Re: Ballistic Theory and the Sagnac Experiment
From: ""
Date: 8 Mar 2006 20:04:47 -0800
Newsgroups: sci.astro, sci.physics.relativity, sci.physics
George Dishman wrote:
> jgreenfield@xxxxxxxxxxx wrote:
> > 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
>
> Yes Jim, (2) IS a red herring, I asked you to
> compare (1) with (3). The Doppler Effect refers
> to a specific mecahnism that alters the rate
> of arrival of the bullets and in order to answer
> my question, you will have to think about the
> situation. You cannot claim the rate difference
> is due to changes of energy because the
> question is constructed so that the energy is
> the same.

"Constructed" is right!!!!!!!
(2) We bin because it is a dead fish!
(3) REQUIRES that the source STOPS to emit a photon.
If you maintain that THAT is what happens, then don't fire me;
I quit
>
> > 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 ...
>
> So do we all in this case and of course energy is
> conserved in all four pictures. Where the bullets
> travel faster, they simply penetrate more deeply
> into the target.

FYI that REQUIRES more energy!!!!!!!!!
>
> "The Doppler Effect" refers to the rate of arrival, not
> the depth of penetration. I want to discuss energy
> soon, as well as how this applies to the signals
> from pulsars, but you need to learn thse basics first.
>
> I'm not going to try again Jim, if you are unwilling
> even to make an attempt at answering my simple
> question without trolling it out for weeks, I'll leave
> it at that.
> 
> George

Bye
Jim G
c'=c+v


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