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correct transversal Doppler shift

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  correct transversal Doppler shift Alsor <alsorgzl@gmail.com> - 2022-07-09 04:47 -0700
    Re: correct transversal Doppler shift Thomas Heger <ttt_heg@web.de> - 2022-07-10 09:05 +0200
      Re: correct transversal Doppler shift Thomas Heger <ttt_heg@web.de> - 2022-07-11 09:21 +0200
        Re: correct transversal Doppler shift Thomas Heger <ttt_heg@web.de> - 2022-08-02 08:52 +0200
          Re: correct transversal Doppler shift Prokaryotic Capase Homolog <prokaryotic.caspase.homolog@gmail.com> - 2022-08-02 00:29 -0700
            Re: correct transversal Doppler shift Thomas Heger <ttt_heg@web.de> - 2022-08-03 09:08 +0200
              Re: correct transversal Doppler shift Volney <volney@invalid.invalid> - 2022-08-03 04:33 -0400
                Re: correct transversal Doppler shift Thomas Heger <ttt_heg@web.de> - 2022-08-04 08:01 +0200
                  Re: correct transversal Doppler shift Prokaryotic Capase Homolog <prokaryotic.caspase.homolog@gmail.com> - 2022-08-04 00:05 -0700
                    Re: correct transversal Doppler shift Maciej Wozniak <maluwozniak@gmail.com> - 2022-08-04 00:11 -0700
                    Re: correct transversal Doppler shift Alsor <alsorgzl@gmail.com> - 2022-08-04 07:37 -0700
                      Re: correct transversal Doppler shift Prokaryotic Capase Homolog <prokaryotic.caspase.homolog@gmail.com> - 2022-08-04 08:04 -0700
                        Re: correct transversal Doppler shift Richard Hachel <r.hachel@tiscali.fr> - 2022-08-04 15:16 +0000
                        Re: correct transversal Doppler shift Alsor <alsorgzl@gmail.com> - 2022-08-04 08:21 -0700
                          Re: correct transversal Doppler shift Richard Hachel <r.hachel@tiscali.fr> - 2022-08-04 15:27 +0000
                          Re: correct transversal Doppler shift Prokaryotic Capase Homolog <prokaryotic.caspase.homolog@gmail.com> - 2022-08-04 08:59 -0700
                            Re: correct transversal Doppler shift Alsor <alsorgzl@gmail.com> - 2022-08-04 09:12 -0700
                    Re: correct transversal Doppler shift Thomas Heger <ttt_heg@web.de> - 2022-08-05 07:08 +0200
                      Re: correct transversal Doppler shift Prokaryotic Capase Homolog <prokaryotic.caspase.homolog@gmail.com> - 2022-08-05 03:29 -0700
                        Re: correct transversal Doppler shift Thomas Heger <ttt_heg@web.de> - 2022-08-06 10:35 +0200
                          Re: correct transversal Doppler shift Prokaryotic Capase Homolog <prokaryotic.caspase.homolog@gmail.com> - 2022-08-06 02:03 -0700
                            Re: correct transversal Doppler shift Maciej Wozniak <maluwozniak@gmail.com> - 2022-08-06 02:26 -0700
                            Re: correct transversal Doppler shift Alsor <alsorgzl@gmail.com> - 2022-08-06 06:06 -0700
                              Re: correct transversal Doppler shift Thomas Heger <ttt_heg@web.de> - 2022-08-07 07:18 +0200
                                Re: correct transversal Doppler shift Alsor <alsorgzl@gmail.com> - 2022-08-07 03:27 -0700
                                  Re: correct transversal Doppler shift Thomas Heger <ttt_heg@web.de> - 2022-08-08 08:45 +0200
                                    Re: correct transversal Doppler shift "Ross A. Finlayson" <ross.finlayson@gmail.com> - 2022-08-08 08:51 -0700
                                    Re: correct transversal Doppler shift Diego Traversa <toed@iavdattg.ev> - 2022-08-08 22:35 +0000
                                      Re: correct transversal Doppler shift "Ross A. Finlayson" <ross.finlayson@gmail.com> - 2022-08-08 21:01 -0700
                      Re: correct transversal Doppler shift Prokaryotic Capase Homolog <prokaryotic.caspase.homolog@gmail.com> - 2022-08-05 03:33 -0700
                    Re: correct transversal Doppler shift "Ross A. Finlayson" <ross.finlayson@gmail.com> - 2022-08-05 21:10 -0700
              Re: correct transversal Doppler shift Alsor <alsorgzl@gmail.com> - 2022-08-03 09:59 -0700
              Re: correct transversal Doppler shift Prokaryotic Capase Homolog <prokaryotic.caspase.homolog@gmail.com> - 2022-08-03 10:12 -0700
    Re: correct transversal Doppler shift Alsor <alsorgzl@gmail.com> - 2022-07-10 06:43 -0700
      Re: correct transversal Doppler shift Richard Hachel <r.hachel@tiscali.fr> - 2022-07-10 16:34 +0000
    Re: correct transversal Doppler shift Tom Roberts <tjroberts137@sbcglobal.net> - 2022-07-13 11:02 -0500
      Re: correct transversal Doppler shift Alsor <alsorgzl@gmail.com> - 2022-07-13 09:28 -0700
        Re: correct transversal Doppler shift Alsor <alsorgzl@gmail.com> - 2022-07-13 09:36 -0700
        Re: correct transversal Doppler shift Richard Hachel <r.hachel@tiscali.fr> - 2022-07-13 18:55 +0000
        Re: correct transversal Doppler shift Tom Roberts <tjroberts137@sbcglobal.net> - 2022-07-18 20:55 -0500
          Re: correct transversal Doppler shift Alsor <alsorgzl@gmail.com> - 2022-07-19 08:13 -0700
            Re: correct transversal Doppler shift Tom Roberts <tjroberts137@sbcglobal.net> - 2022-07-20 11:28 -0500
              Re: correct transversal Doppler shift Alsor <alsorgzl@gmail.com> - 2022-07-20 12:03 -0700
              Re: correct transversal Doppler shift Alsor <alsorgzl@gmail.com> - 2022-07-20 13:04 -0700
                Re: correct transversal Doppler shift Tom Roberts <tjroberts137@sbcglobal.net> - 2022-07-21 21:19 -0500
                  Re: correct transversal Doppler shift Alsor <alsorgzl@gmail.com> - 2022-07-22 07:28 -0700
                    Re: correct transversal Doppler shift Tom Roberts <tjroberts137@sbcglobal.net> - 2022-07-22 12:11 -0500
                    Re: correct transversal Doppler shift Richard Hachel <r.hachel@tiscali.fr> - 2022-07-22 17:19 +0000
            Re: correct transversal Doppler shift Richard Hachel <r.hachel@tiscali.fr> - 2022-07-22 22:44 +0000
              Re: correct transversal Doppler shift Alsor <alsorgzl@gmail.com> - 2022-07-23 04:46 -0700
                Re: correct transversal Doppler shift Alsor <alsorgzl@gmail.com> - 2022-07-23 04:59 -0700
                  Re: correct transversal Doppler shift Richard Hachel <r.hachel@tiscali.fr> - 2022-07-23 14:34 +0000
                Re: correct transversal Doppler shift Richard Hachel <r.hachel@tiscali.fr> - 2022-07-23 12:20 +0000
        Re: correct transversal Doppler shift Prokaryotic Capase Homolog <prokaryotic.caspase.homolog@gmail.com> - 2022-07-29 21:27 -0700
          Re: correct transversal Doppler shift Prokaryotic Capase Homolog <prokaryotic.caspase.homolog@gmail.com> - 2022-07-29 21:59 -0700
          Re: correct transversal Doppler shift Richard Hachel <r.hachel@tiscali.fr> - 2022-07-30 11:26 +0000
          Re: correct transversal Doppler shift Alsor <alsorgzl@gmail.com> - 2022-07-30 05:34 -0700
      Re: correct transversal Doppler shift Richard Hachel <r.hachel@tiscali.fr> - 2022-07-13 18:51 +0000
        Re: correct transversal Doppler shift Tom Roberts <tjroberts137@sbcglobal.net> - 2022-07-20 12:12 -0500
    Re: correct transversal Doppler shift "mitchr...@gmail.com" <mitchrae3323@gmail.com> - 2022-08-04 16:06 -0700
      Re: correct transversal Doppler shift Duan Bonomo <ddfs@dtszpmat.zy> - 2022-08-06 16:15 +0000
        Re: correct transversal Doppler shift Alsor <alsorgzl@gmail.com> - 2022-08-06 11:25 -0700
          Re: correct transversal Doppler shift Thomas Heger <ttt_heg@web.de> - 2022-08-07 07:25 +0200
    Re: correct transversal Doppler shift "erkd...@gmail.com" <erkdemon@gmail.com> - 2022-08-06 22:11 -0700

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#588141 — correct transversal Doppler shift

The Doppler shift for angle 90 degs at receiver is blue not red:

The general formula:

d = k(1-v/c cosf); k = 1/sqrt(1-v^2/c^2)

for transverse Doppler f = 90, cos90 = 0:

d = k = 1/sqrt(1-v^2/c^2);
this is a bule shift!

The energy of moving atom is equal:
E = m0 c^2 gamma

Simple: the moving atoms emit bigger energy,
proportional to its total energy, which is gamma times bigger.


Where is the red shift?

it's for angle cosf = v/c:

d = k (1-v^2/c^2) = k/k^2 = 1/k = sqrt(1-v^2/c^2)

...........

Total energy emitted by moving source is gamma times more, not less.

forward + backward emission =
sqrt(1+v)/(1-v) + sqrt(1-v/1+v) = 
sqrt(1-v^2) [1/1-v + 1/1+v] = 

sqrt(1-v^2) (1+v + 1-v)/(1-v^2) = 2/sqrt(1-v^2)

the mean quantity is: 1/sqrt...
bigger gamma times, not less!

There is no dilation of energy of moving sources -
 the energy is bigger, always.

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#588192

Am 09.07.2022 um 13:47 schrieb Alsor:
> The Doppler shift for angle 90 degs at receiver is blue not red:
>
> The general formula:
>
> d = k(1-v/c cosf); k = 1/sqrt(1-v^2/c^2)
>
> for transverse Doppler f = 90, cos90 = 0:
>
> d = k = 1/sqrt(1-v^2/c^2);
> this is a blue shift!


Well, yes, because something approaching the receiver from - say- the 
left side, passes by at right angles and receedes to the right, would 
approach the receiver in the first case, what causes a blue-shift. In 
the other case we get a red-shift.

The Doppler effect is about the change of the distance, hence only a 
single point has no change of frequency, while in the approach the 
distance changes and also on the other side, where the objects moves away.

At a certain moment this would change from approaching to receeding and 
that is the case, where that thing passes by at right angles (at least 
in the realm of slow velocities).

TH
...

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#588247

Am 10.07.2022 um 09:05 schrieb Thomas Heger:
> Am 09.07.2022 um 13:47 schrieb Alsor:
>> The Doppler shift for angle 90 degs at receiver is blue not red:
>>
>> The general formula:
>>
>> d = k(1-v/c cosf); k = 1/sqrt(1-v^2/c^2)
>>
>> for transverse Doppler f = 90, cos90 = 0:
>>
>> d = k = 1/sqrt(1-v^2/c^2);
>> this is a blue shift!
>
>
> Well, yes, because something approaching the receiver from - say- the
> left side, passes by at right angles and receedes to the right, would
> approach the receiver in the first case, what causes a blue-shift. In
> the other case we get a red-shift.
>
> The Doppler effect is about the change of the distance, hence only a
> single point has no change of frequency, while in the approach the
> distance changes and also on the other side, where the objects moves away.


The Doppler shift is caused by the changing distance, if an emitter is 
aproaching a receiver.

The effect stems from the fact, that with shorter distance the time 
needed for the signal to travel from emitter to receiver gets smaller.

This causes a frequency shift of the signal at the side of the receiver, 
while the emitter sends with constant frequency. That's why the Doppler 
effect is only visible at the side of the receiver.

The direction is less relevant, if the distance changes at a certain rate.

That's why the effect does not primarily depend on an angle, but on the 
change of the distance.

At the point of right angles between the line from emitter to receiver 
towards the path of the emitter (what you have called 'traverse case'), 
there is obviously no change of distance, hence the Doppler effect is 
momentarily zero.

...


TH
>

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#589075

Am 11.07.2022 um 09:21 schrieb Thomas Heger:
> Am 10.07.2022 um 09:05 schrieb Thomas Heger:
>> Am 09.07.2022 um 13:47 schrieb Alsor:
>>> The Doppler shift for angle 90 degs at receiver is blue not red:
>>>
>>> The general formula:
>>>
>>> d = k(1-v/c cosf); k = 1/sqrt(1-v^2/c^2)
>>>
>>> for transverse Doppler f = 90, cos90 = 0:
>>>
>>> d = k = 1/sqrt(1-v^2/c^2);
>>> this is a blue shift!
>>
>>
>> Well, yes, because something approaching the receiver from - say- the
>> left side, passes by at right angles and receedes to the right, would
>> approach the receiver in the first case, what causes a blue-shift. In
>> the other case we get a red-shift.
>>
>> The Doppler effect is about the change of the distance, hence only a
>> single point has no change of frequency, while in the approach the
>> distance changes and also on the other side, where the objects moves
>> away.
>
>
> The Doppler shift is caused by the changing distance, if an emitter is
> aproaching a receiver.
>
> The effect stems from the fact, that with shorter distance the time
> needed for the signal to travel from emitter to receiver gets smaller.
>
> This causes a frequency shift of the signal at the side of the receiver,
> while the emitter sends with constant frequency. That's why the Doppler
> effect is only visible at the side of the receiver.
>
> The direction is less relevant, if the distance changes at a certain rate.
>
> That's why the effect does not primarily depend on an angle, but on the
> change of the distance.
>
> At the point of right angles between the line from emitter to receiver
> towards the path of the emitter (what you have called 'traverse case'),
> there is obviously no change of distance, hence the Doppler effect is
> momentarily zero.
>
> ...
If you imagine the sound of a race car passing by on a track, you would 
hear a certain distzinctive frequency change.

It goes like
iiiieeoouuuuhh

(something like that....)

The 'blue-shift' side is, where the car approaches and the 'red-shift' 
occurs, where the car recedes.

But the 'transver case' is apparently coming with a zero frequency 
shift, because that is the point, where frequency shift turns from red- 
to blue-shift.

The mid-point must be obviously zero-shift.

Now this point can possibly become distorted by motion, too, at least a bit.

TH

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#589077

On Tuesday, August 2, 2022 at 1:53:01 AM UTC-5, Thomas Heger wrote:
> If you imagine the sound of a race car passing by on a track, you would 
> hear a certain distzinctive frequency change. 
> 
> It goes like 
> iiiieeoouuuuhh 
> 
> (something like that....) 
> 
> The 'blue-shift' side is, where the car approaches and the 'red-shift' 
> occurs, where the car recedes. 
> 
> But the 'transver case' is apparently coming with a zero frequency 
> shift, because that is the point, where frequency shift turns from red- 
> to blue-shift. 
> 
> The mid-point must be obviously zero-shift. 

Sloppy thinking, as usual. What is the "mid-point"?

What is the red/blue Doppler shift of the race car when it is 
GEOMETRICALLY the nearest to you, the spectator?

What is the red/blue Doppler shift of the race car when you SEE it at
its closest point?

Now apply this to a spaceship traveling at a large fraction of the speed
of light.

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#589148

Am 02.08.2022 um 09:29 schrieb Prokaryotic Capase Homolog:
> On Tuesday, August 2, 2022 at 1:53:01 AM UTC-5, Thomas Heger wrote:
>> If you imagine the sound of a race car passing by on a track, you would
>> hear a certain distzinctive frequency change.
>>
>> It goes like
>> iiiieeoouuuuhh
>>
>> (something like that....)
>>
>> The 'blue-shift' side is, where the car approaches and the 'red-shift'
>> occurs, where the car recedes.
>>
>> But the 'transver case' is apparently coming with a zero frequency
>> shift, because that is the point, where frequency shift turns from red-
>> to blue-shift.
>>
>> The mid-point must be obviously zero-shift.
>
> Sloppy thinking, as usual. What is the "mid-point"?


The meant 'mid-point' in a function graph is an extreme point, where the 
tangent is horizontal.

Now we take the change-of-frequency-function of the received sound of 
the race car as function value and plot it on the y_axis. The distance 
is plotted on the x-axis and the car paces from left to right.

The mid point is now the point, where that path of the car is 
perpendicular to my line of sight upon the race track.

At this point the car moves perpendicular to my distance to the path, 
what is called 'transversal movement'.

Now we know from experience, that the Doppler effect at this point is 
zero, because the  'change-of-frequency-function' is switching there 
from positive to negative.

> What is the red/blue Doppler shift of the race car when it is
> GEOMETRICALLY the nearest to you, the spectator?

Zero

It must be zero, because at this point the car changes from approaching 
to receding.

This is also a change from blue- to red-shift, or, if you prefer that, 
from higher tone to lower tone.

> What is the red/blue Doppler shift of the race car when you SEE it at
> its closest point?

I would suggest to stick to sound. Light is also effected by the Doppler 
effect, but it takes other means than ears to measure that.

> Now apply this to a spaceship traveling at a large fraction of the speed
> of light.

Spaceships cannot do this, because velocity requires a point of 
reference, against which velocity is measured (assumed that space is 
devoid of usable reference points).


TH

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#589152

On 8/3/2022 3:08 AM, Thomas Heger wrote:
> Am 02.08.2022 um 09:29 schrieb Prokaryotic Capase Homolog:
>> On Tuesday, August 2, 2022 at 1:53:01 AM UTC-5, Thomas Heger wrote:
>>> If you imagine the sound of a race car passing by on a track, you would
>>> hear a certain distzinctive frequency change.
>>>
>>> It goes like
>>> iiiieeoouuuuhh
>>>
>>> (something like that....)
>>>
>>> The 'blue-shift' side is, where the car approaches and the 'red-shift'
>>> occurs, where the car recedes.
>>>
>>> But the 'transver case' is apparently coming with a zero frequency
>>> shift, because that is the point, where frequency shift turns from red-
>>> to blue-shift.
>>>
>>> The mid-point must be obviously zero-shift.
>>
>> Sloppy thinking, as usual. What is the "mid-point"?
> 
> 
> The meant 'mid-point' in a function graph is an extreme point, where the 
> tangent is horizontal.

As seen by the race car or by the observer?
> 
> Now we take the change-of-frequency-function of the received sound of 
> the race car as function value and plot it on the y_axis. The distance 
> is plotted on the x-axis and the car paces from left to right.
> 
> The mid point is now the point, where that path of the car is 
> perpendicular to my line of sight upon the race track.
> 
> At this point the car moves perpendicular to my distance to the path, 
> what is called 'transversal movement'.

As seen by whom?
With sound, the position uses a near-infinite speed of light for 
comparisons so it really doesn't matter, but obviously the speed of 
light is not infinite compared to the speed of light.
> 
> Now we know from experience, that the Doppler effect at this point is 
> zero, because the  'change-of-frequency-function' is switching there 
> from positive to negative.
> 
>> What is the red/blue Doppler shift of the race car when it is
>> GEOMETRICALLY the nearest to you, the spectator?
> 
> Zero
> 
> It must be zero, because at this point the car changes from approaching 
> to receding.

Careful.... (see above)
> 
> This is also a change from blue- to red-shift, or, if you prefer that, 
> from higher tone to lower tone.
> 
>> What is the red/blue Doppler shift of the race car when you SEE it at
>> its closest point?
> 
> I would suggest to stick to sound. Light is also effected by the Doppler 
> effect, but it takes other means than ears to measure that.

You are waving your hands to shoo the finite speed of light away.
> 
>> Now apply this to a spaceship traveling at a large fraction of the speed
>> of light.
> 
> Spaceships cannot do this, because velocity requires a point of 
> reference, against which velocity is measured (assumed that space is 
> devoid of usable reference points).

Duh-h-h-h!!! With reference to the observer observing the spaceship, of 
course!

As the spaceship whizzes by the observer at a large fraction of the 
speed of light, there will be a point where light is emitted which is 
received by the observer when the spaceship is at its closest approach, 
and the light emitted at closest approach which won't be seen by the 
observer until the rocket is receding.  (all this is from the top of my 
head, I haven't figured in the complications of length contractions/time 
dilations other than the relativistic Doppler effect itself)
> 
> 
> TH
> 

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#589232

Am 03.08.2022 um 10:33 schrieb Volney:

>>>> If you imagine the sound of a race car passing by on a track, you would
>>>> hear a certain distzinctive frequency change.
>>>>
>>>> It goes like
>>>> iiiieeoouuuuhh
>>>>
>>>> (something like that....)
>>>>
>>>> The 'blue-shift' side is, where the car approaches and the 'red-shift'
>>>> occurs, where the car recedes.
>>>>
>>>> But the 'transver case' is apparently coming with a zero frequency
>>>> shift, because that is the point, where frequency shift turns from red-
>>>> to blue-shift.
>>>>
>>>> The mid-point must be obviously zero-shift.
>>>
>>> Sloppy thinking, as usual. What is the "mid-point"?
>>
>>
>> The meant 'mid-point' in a function graph is an extreme point, where
>> the tangent is horizontal.
>
> As seen by the race car or by the observer?

Obviously meant was 'observer'.

The Doppler effect is only present at the side of the observer, because 
the emitter does not move in respect to himself.

>> Now we take the change-of-frequency-function of the received sound of
>> the race car as function value and plot it on the y_axis. The distance
>> is plotted on the x-axis and the car paces from left to right.
>>
>> The mid point is now the point, where that path of the car is
>> perpendicular to my line of sight upon the race track.
>>
>> At this point the car moves perpendicular to my distance to the path,
>> what is called 'transversal movement'.
>
> As seen by whom?
Seen by an observer watching a race car pacing along some race-track.

> With sound, the position uses a near-infinite speed of light for
> comparisons so it really doesn't matter, but obviously the speed of
> light is not infinite compared to the speed of light.

I have already suggested, that 'mid-point' could eventually require a 
'relativistic correction', because that line of sight is based on light 
and that has a finite speed.

That would require a tiny correction of the mid point, but which is 
insignificant here.

>>
>> Now we know from experience, that the Doppler effect at this point is
>> zero, because the  'change-of-frequency-function' is switching there
>> from positive to negative.
>>
>>> What is the red/blue Doppler shift of the race car when it is
>>> GEOMETRICALLY the nearest to you, the spectator?
>>
>> Zero
>>
>> It must be zero, because at this point the car changes from
>> approaching to receding.
>
> Careful.... (see above)


OK. 'To be careful' is always a good idea.

>> This is also a change from blue- to red-shift, or, if you prefer that,
>> from higher tone to lower tone.
>>
>>> What is the red/blue Doppler shift of the race car when you SEE it at
>>> its closest point?
>>
>> I would suggest to stick to sound. Light is also effected by the
>> Doppler effect, but it takes other means than ears to measure that.
>
> You are waving your hands to shoo the finite speed of light away.

No, I have used sound as an example for the Doppler effect, which is in 
the range of human abillities and an everyday experience.

The transversal Doppler effect for sound is therefor zero at the point, 
where the change of distance is momentarily zero. This point is the 
point, where the observer looks in right angles towards the racetrack.

>>> Now apply this to a spaceship traveling at a large fraction of the speed
>>> of light.
>>
>> Spaceships cannot do this, because velocity requires a point of
>> reference, against which velocity is measured (assumed that space is
>> devoid of usable reference points).
>
> Duh-h-h-h!!! With reference to the observer observing the spaceship, of
> course!

If you want an observer observing another spaceship from his own 
spaceship, than this is certainly possible, but you need to mention that.

But you didn't, but mentioned only a single spaceship.

...


TH

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#589233

On Thursday, August 4, 2022 at 1:01:24 AM UTC-5, Thomas Heger wrote:

> The transversal Doppler effect for sound is therefor zero at the point, 
> where the change of distance is momentarily zero. This point is the 
> point, where the observer looks in right angles towards the racetrack.

1) Let us take a race car "r" traveling at Mach 0.2.
2) You, the observer "o", are standing one mile from the road.
3) Sound travels 5 sec from the road to your ears at its closest point. 
4) As the car crosses your path, you do not hear sound from where
    the car is NOW, but from where it was about 5 seconds ago "e". 
5) The sound that you hear from "e" is Doppler shifted to a higher tone.

-------e--r----------
----------|----------
----------|----------
----------|----------
----------|----------
----------|----------
----------o----------

Let us try two more scenarios:
1) You are standing at the center of a circular  track and a race car
     is driving around you at high speed. Is the sound that you hear
     Doppler shifted and if so, is it to a higher or lower tone?
2) You are driving a race car around a circular track with a loudspeaker
     at the center. Is the sound that you hear Doppler shifted and if so, 
     is it to a higher or lower tone?

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#589234

On Thursday, 4 August 2022 at 09:05:52 UTC+2, prokaryotic.c...@gmail.com wrote:
> On Thursday, August 4, 2022 at 1:01:24 AM UTC-5, Thomas Heger wrote: 
> 
> > The transversal Doppler effect for sound is therefor zero at the point, 
> > where the change of distance is momentarily zero. This point is the 
> > point, where the observer looks in right angles towards the racetrack.
> 1) Let us take a race car "r" traveling at Mach 0.2. 
> 2) You, the observer "o", are standing one mile from the road. 
> 3) Sound travels 5 sec from the road to your ears at its closest point. 
> 4) As the car crosses your path, you do not hear sound from where 
> the car is NOW, but from where it was about 5 seconds ago "e". 
> 5) The sound that you hear from "e" is Doppler shifted to a higher tone. 
> 
> -------e--r---------- 
> ----------|---------- 
> ----------|---------- 
> ----------|---------- 
> ----------|---------- 
> ----------|---------- 
> ----------o---------- 
> 
> Let us try two more scenarios: 

Let's finish with scenarrios and take a look
into the reality, where forbidden by your bunch of 
idiots GPS and TAI keep measuring t'=t, just
like all serious clocks always did.

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#589251

czwartek, 4 sierpnia 2022 o 09:05:52 UTC+2 prokaryotic.c...@gmail.com napisał(a):
> On Thursday, August 4, 2022 at 1:01:24 AM UTC-5, Thomas Heger wrote: 
> 
> > The transversal Doppler effect for sound is therefor zero at the point, 
> > where the change of distance is momentarily zero. This point is the 
> > point, where the observer looks in right angles towards the racetrack.
> 1) Let us take a race car "r" traveling at Mach 0.2. 
> 2) You, the observer "o", are standing one mile from the road. 
> 3) Sound travels 5 sec from the road to your ears at its closest point. 
> 4) As the car crosses your path, you do not hear sound from where 
> the car is NOW, but from where it was about 5 seconds ago "e". 
> 5) The sound that you hear from "e" is Doppler shifted to a higher tone. 
> 
> -------e--r---------- 
> ----------|---------- 
> ----------|---------- 
> ----------|---------- 
> ----------|---------- 
> ----------|---------- 
> ----------o---------- 
> 
> Let us try two more scenarios: 
> 1) You are standing at the center of a circular track and a race car 
> is driving around you at high speed. Is the sound that you hear 
> Doppler shifted and if so, is it to a higher or lower tone? 
> 2) You are driving a race car around a circular track with a loudspeaker 
> at the center. Is the sound that you hear Doppler shifted and if so, 
> is it to a higher or lower tone?

Where is a star which Bradley used to measure aberration of light?

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#589255

On Thursday, August 4, 2022 at 9:37:58 AM UTC-5, Alsor wrote:
> czwartek, 4 sierpnia 2022 o 09:05:52 UTC+2 prokaryotic.c...@gmail.com napisał(a): 
> > On Thursday, August 4, 2022 at 1:01:24 AM UTC-5, Thomas Heger wrote: 
> > 
> > > The transversal Doppler effect for sound is therefor zero at the point, 
> > > where the change of distance is momentarily zero. This point is the 
> > > point, where the observer looks in right angles towards the racetrack. 
> > 1) Let us take a race car "r" traveling at Mach 0.2. 
> > 2) You, the observer "o", are standing one mile from the road. 
> > 3) Sound travels 5 sec from the road to your ears at its closest point. 
> > 4) As the car crosses your path, you do not hear sound from where 
> > the car is NOW, but from where it was about 5 seconds ago "e". 
> > 5) The sound that you hear from "e" is Doppler shifted to a higher tone. 
> > 
> > -------e--r---------- 
> > ----------|---------- 
> > ----------|---------- 
> > ----------|---------- 
> > ----------|---------- 
> > ----------|---------- 
> > ----------o---------- 
> > 
> > Let us try two more scenarios: 
> > 1) You are standing at the center of a circular track and a race car 
> > is driving around you at high speed. Is the sound that you hear 
> > Doppler shifted and if so, is it to a higher or lower tone? 
> > 2) You are driving a race car around a circular track with a loudspeaker 
> > at the center. Is the sound that you hear Doppler shifted and if so, 
> > is it to a higher or lower tone?
> Where is a star which Bradley used to measure aberration of light?

I'm not sure what you mean. 
But see this section which I wrote and illustrated:
https://en.wikipedia.org/wiki/Special_relativity#Relativistic_aberration_of_light

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#589257

Le 04/08/2022 à 17:05, Prokaryotic Capase Homolog a écrit :
> On Thursday, August 4, 2022 at 9:37:58 AM UTC-5, Alsor wrote:
>> czwartek, 4 sierpnia 2022 o 09:05:52 UTC+2 prokaryotic.c...@gmail.com 
>> napisał(a): 
>> > On Thursday, August 4, 2022 at 1:01:24 AM UTC-5, Thomas Heger wrote: 
>> > 
>> > > The transversal Doppler effect for sound is therefor zero at the point, 
>> > > where the change of distance is momentarily zero. This point is the 
>> > > point, where the observer looks in right angles towards the racetrack. 
>> > 1) Let us take a race car "r" traveling at Mach 0.2. 
>> > 2) You, the observer "o", are standing one mile from the road. 
>> > 3) Sound travels 5 sec from the road to your ears at its closest point. 
>> > 4) As the car crosses your path, you do not hear sound from where 
>> > the car is NOW, but from where it was about 5 seconds ago "e". 
>> > 5) The sound that you hear from "e" is Doppler shifted to a higher tone. 
>> > 
>> > -------e--r---------- 
>> > ----------|---------- 
>> > ----------|---------- 
>> > ----------|---------- 
>> > ----------|---------- 
>> > ----------|---------- 
>> > ----------o---------- 
>> > 
>> > Let us try two more scenarios: 
>> > 1) You are standing at the center of a circular track and a race car 
>> > is driving around you at high speed. Is the sound that you hear 
>> > Doppler shifted and if so, is it to a higher or lower tone? 
>> > 2) You are driving a race car around a circular track with a loudspeaker 
>> > at the center. Is the sound that you hear Doppler shifted and if so, 
>> > is it to a higher or lower tone?
>> Where is a star which Bradley used to measure aberration of light?
> 
> I'm not sure what you mean. 
> But see this section which I wrote and illustrated:
> 
> https://en.wikipedia.org/wiki/Special_relativity#Relativistic_aberration_of_light

In the case of star position aberration (I prefer that term), it suffices 
to correctly apply the Lorentz transformations.

At the zenith, we have a Φ deviation of 20.6" in the direction of the 
earth's movement.

R.H. 

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#589258

czwartek, 4 sierpnia 2022 o 17:05:02 UTC+2 prokaryotic.c...@gmail.com napisał(a):
> On Thursday, August 4, 2022 at 9:37:58 AM UTC-5, Alsor wrote: 
> > czwartek, 4 sierpnia 2022 o 09:05:52 UTC+2 prokaryotic.c...@gmail.com napisał(a): 
> > > On Thursday, August 4, 2022 at 1:01:24 AM UTC-5, Thomas Heger wrote: 
> > > 
> > > > The transversal Doppler effect for sound is therefor zero at the point, 
> > > > where the change of distance is momentarily zero. This point is the 
> > > > point, where the observer looks in right angles towards the racetrack. 
> > > 1) Let us take a race car "r" traveling at Mach 0.2. 
> > > 2) You, the observer "o", are standing one mile from the road. 
> > > 3) Sound travels 5 sec from the road to your ears at its closest point. 
> > > 4) As the car crosses your path, you do not hear sound from where 
> > > the car is NOW, but from where it was about 5 seconds ago "e". 
> > > 5) The sound that you hear from "e" is Doppler shifted to a higher tone. 
> > > 
> > > -------e--r---------- 
> > > ----------|---------- 
> > > ----------|---------- 
> > > ----------|---------- 
> > > ----------|---------- 
> > > ----------|---------- 
> > > ----------o---------- 
> > > 
> > > Let us try two more scenarios: 
> > > 1) You are standing at the center of a circular track and a race car 
> > > is driving around you at high speed. Is the sound that you hear 
> > > Doppler shifted and if so, is it to a higher or lower tone? 
> > > 2) You are driving a race car around a circular track with a loudspeaker 
> > > at the center. Is the sound that you hear Doppler shifted and if so, 
> > > is it to a higher or lower tone? 
> > Where is a star which Bradley used to measure aberration of light?
> I'm not sure what you mean. 
> But see this section which I wrote and illustrated: 
> https://en.wikipedia.org/wiki/Special_relativity#Relativistic_aberration_of_light

I'm talking about correct Doppler, 
because including energy: at emission, and the detected on a receiver.

So, what is the energy of light under typical stellar aberration?
1. the energy is bigger
2. it's lowered
3. the same (as for stationary conditions - without any motion: no aberration, null Doppler)

E_receiver = E_source * ?

Doppler = ?
an angle of observation = ?
a speed of light at receiver = ?

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#589260

Le 04/08/2022 à 17:21, Alsor a écrit :
> czwartek, 4 sierpnia 2022 o 17:05:02 UTC+2 prokaryotic.c...@gmail.com 
> napisał(a):
>> On Thursday, August 4, 2022 at 9:37:58 AM UTC-5, Alsor wrote: 
>> > czwartek, 4 sierpnia 2022 o 09:05:52 UTC+2 prokaryotic.c...@gmail.com 
>> napisał(a): 
>> > > On Thursday, August 4, 2022 at 1:01:24 AM UTC-5, Thomas Heger wrote: 
>> > > 
>> > > > The transversal Doppler effect for sound is therefor zero at the point, 
>> > > > where the change of distance is momentarily zero. This point is the 
>> > > > point, where the observer looks in right angles towards the racetrack. 
>> > > 1) Let us take a race car "r" traveling at Mach 0.2. 
>> > > 2) You, the observer "o", are standing one mile from the road. 
>> > > 3) Sound travels 5 sec from the road to your ears at its closest point. 
>> > > 4) As the car crosses your path, you do not hear sound from where 
>> > > the car is NOW, but from where it was about 5 seconds ago "e". 
>> > > 5) The sound that you hear from "e" is Doppler shifted to a higher tone. 
>> > > 
>> > > -------e--r---------- 
>> > > ----------|---------- 
>> > > ----------|---------- 
>> > > ----------|---------- 
>> > > ----------|---------- 
>> > > ----------|---------- 
>> > > ----------o---------- 
>> > > 
>> > > Let us try two more scenarios: 
>> > > 1) You are standing at the center of a circular track and a race car 
>> > > is driving around you at high speed. Is the sound that you hear 
>> > > Doppler shifted and if so, is it to a higher or lower tone? 
>> > > 2) You are driving a race car around a circular track with a loudspeaker 
>> > > at the center. Is the sound that you hear Doppler shifted and if so, 
>> > > is it to a higher or lower tone? 
>> > Where is a star which Bradley used to measure aberration of light?
>> I'm not sure what you mean. 
>> But see this section which I wrote and illustrated: 
>> 
>> https://en.wikipedia.org/wiki/Special_relativity#Relativistic_aberration_of_light
> 
> I'm talking about correct Doppler, 
> because including energy: at emission, and the detected on a receiver.
> 
> So, what is the energy of light under typical stellar aberration?
> 1. the energy is bigger
> 2. it's lowered
> 3. the same (as for stationary conditions - without any motion: no aberration, 
> null Doppler)
> 
> E_receiver = E_source * ?
> 
> Doppler = ?
> an angle of observation = ?
> a speed of light at receiver = ?

<http://news2.nemoweb.net/jntp?dAvSMZ-f6o5UCBBv1dinIj_rJoI@jntp/Data.Media:1>


R.H.

-- 
"Mais ne nous trompons pas.
 Il n'y a pas que de la violence avec des armes : il y a des situations de 
violence." 
Abbé Pierre
₀₀₀
<http://news2.nemoweb.net/?DataID=dAvSMZ-f6o5UCBBv1dinIj_rJoI@jntp>

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#589261

On Thursday, August 4, 2022 at 10:21:23 AM UTC-5, Alsor wrote:
> czwartek, 4 sierpnia 2022 o 17:05:02 UTC+2 prokaryotic.c...@gmail.com napisał(a): 
> > On Thursday, August 4, 2022 at 9:37:58 AM UTC-5, Alsor wrote: 

> > > Where is a star which Bradley used to measure aberration of light? 
> > I'm not sure what you mean. 
> > But see this section which I wrote and illustrated: 
> > https://en.wikipedia.org/wiki/Special_relativity#Relativistic_aberration_of_light
> I'm talking about correct Doppler, 
> because including energy: at emission, and the detected on a receiver. 
> 
> So, what is the energy of light under typical stellar aberration? 

Relativistic Doppler effect and aberration are closely related phenomena.
I am 76.8% author of the Wikipedia article on Relativistic Doppler effect,
and that article has most of what I would have to say on this:
https://en.wikipedia.org/wiki/Relativistic_Doppler_effect

Very specifically, I did NOT write the sections on
- Relativistic longitudinal Doppler effect
- Doppler effect on intensity
nor did I draw Figures 1 or 8. Everything else, however, is mostly
mine.

I don't know what you mean by "typical" stellar aberration. It depends
on the angle of the star and the velocity of the Earth in its orbit. 
Figure 8 illustrates things qualitatively, and the rest of the text provides
applicable equations that will enable you to compute most typical
textbook scenarios.

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#589262

czwartek, 4 sierpnia 2022 o 17:59:04 UTC+2 prokaryotic.c...@gmail.com napisał(a):
> On Thursday, August 4, 2022 at 10:21:23 AM UTC-5, Alsor wrote:
> > czwartek, 4 sierpnia 2022 o 17:05:02 UTC+2 prokaryotic.c...@gmail.com napisał(a): 
> > > On Thursday, August 4, 2022 at 9:37:58 AM UTC-5, Alsor wrote: 
> 
> > > > Where is a star which Bradley used to measure aberration of light? 
> > > I'm not sure what you mean. 
> > > But see this section which I wrote and illustrated: 
> > > https://en.wikipedia.org/wiki/Special_relativity#Relativistic_aberration_of_light 
> > I'm talking about correct Doppler, 
> > because including energy: at emission, and the detected on a receiver. 
> > 
> > So, what is the energy of light under typical stellar aberration?
> Relativistic Doppler effect and aberration are closely related phenomena. 
> I am 76.8% author of the Wikipedia article on Relativistic Doppler effect, 
> and that article has most of what I would have to say on this: 
> https://en.wikipedia.org/wiki/Relativistic_Doppler_effect 
> 
> Very specifically, I did NOT write the sections on
> - Relativistic longitudinal Doppler effect
> - Doppler effect on intensity
> nor did I draw Figures 1 or 8. Everything else, however, is mostly 
> mine. 
> 
> I don't know what you mean by "typical" stellar aberration. It depends 
> on the angle of the star and the velocity of the Earth in its orbit. 
> Figure 8 illustrates things qualitatively, and the rest of the text provides 
> applicable equations that will enable you to compute most typical 
> textbook scenarios.

A told about the simplest case: 90 degs for distant star emission.

You can get any angle, but in this case... the whole discussion lands about angles... probably.

So, we assume the local conditions, hence:
cosf' = (cosf - v/c)/(1 - v/c cosf);

for f = 90, this gives: cosf' = -v/c,
so it's simple...

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#589287

Am 04.08.2022 um 09:05 schrieb Prokaryotic Capase Homolog:
> On Thursday, August 4, 2022 at 1:01:24 AM UTC-5, Thomas Heger wrote:
>
>> The transversal Doppler effect for sound is therefor zero at the point,
>> where the change of distance is momentarily zero. This point is the
>> point, where the observer looks in right angles towards the racetrack.
>
> 1) Let us take a race car "r" traveling at Mach 0.2.
> 2) You, the observer "o", are standing one mile from the road.
No, I'm sitting twenty meters away from the track.

> 3) Sound travels 5 sec from the road to your ears at its closest point.
> 4) As the car crosses your path, you do not hear sound from where
>      the car is NOW, but from where it was about 5 seconds ago "e".

I'm not a bat and cannot see by the ears.
Actually I see light and use my eyes for that purpose.

The delay for the finite speed of light needed to be considered, even if 
very small.

But in this example it is totally irelevant, because the track does not 
move and determins, where the race-car can go.

> 5) The sound that you hear from "e" is Doppler shifted to a higher tone.
>
> -------e--r----------
> ----------|----------
> ----------|----------
> ----------|----------
> ----------|----------
> ----------|----------
> ----------o----------
>
> Let us try two more scenarios:
> 1) You are standing at the center of a circular  track and a race car
>       is driving around you at high speed. Is the sound that you hear
>       Doppler shifted and if so, is it to a higher or lower tone?

I would prefer a linear track.

The tone is higher on the side of the approach und lower on the receding 
side, where the car drives away.

> 2) You are driving a race car around a circular track with a loudspeaker
>       at the center. Is the sound that you hear Doppler shifted and if so,
>       is it to a higher or lower tone?

No, I would always hear the same frequency, because the distance is the 
important part and does not change in this example, if the speeds are 
moderatly low.

At very high velocities this is not the case anymore, because the path 
of the heard wave gets curved.

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#589296

On Friday, August 5, 2022 at 12:08:33 AM UTC-5, Thomas Heger wrote:
> Am 04.08.2022 um 09:05 schrieb Prokaryotic Capase Homolog: 
> > 
> > 1) Let us take a race car "r" traveling at Mach 0.2. 
> > 2) You, the observer "o", are standing one mile from the road.
> No, I'm sitting twenty meters away from the track.
> > 3) Sound travels 5 sec from the road to your ears at its closest point. 
> > 4) As the car crosses your path, you do not hear sound from where 
> > the car is NOW, but from where it was about 5 seconds ago "e".
> I'm not a bat and cannot see by the ears.
> Actually I see light and use my eyes for that purpose. 

You do not hear with your ears. Stay on topic.
 
> The delay for the finite speed of light needed to be considered, even if 
> very small. 

For sonic transverse Doppler shift, it makes hardly any difference.

For optical transverse Doppler shift, it is a different story. 
 
> But in this example it is totally irelevant, because the track does not 
> move and determins, where the race-car can go.
> > 5) The sound that you hear from "e" is Doppler shifted to a higher tone. 
> > 
> > -------e--r---------- 
> > ----------|---------- 
> > ----------|---------- 
> > ----------|---------- 
> > ----------|---------- 
> > ----------|---------- 
> > ----------o---------- 
 
In summary, whether the race car is *geometrically* at its
closest point, or one *sees* the race car at its closest
point, the overall effect is the same: One hears the sound
of the race car Doppler-shifted to higher notes. 

> > Let us try two more scenarios: 
> > 1) You are standing at the center of a circular track and a race car 
> > is driving around you at high speed. Is the sound that you hear 
> > Doppler shifted and if so, is it to a higher or lower tone?
> I would prefer a linear track. 
> 
> The tone is higher on the side of the approach und lower on the receding 
> side, where the car drives away.

CIRCULAR track!!! At no point does the race car have any
longitudinal motion with respect to you at the center.
At race car speeds, one measures no significant sonic
Doppler shift. 

> > 2) You are driving a race car around a circular track with a loudspeaker 
> > at the center. Is the sound that you hear Doppler shifted and if so, 
> > is it to a higher or lower tone?
> No, I would always hear the same frequency, because the distance is the 
> important part and does not change in this example, if the speeds are 
> moderatly low. 

Finally, you get one correct. At ordinary race car speeds, 
one measures no significant sonic Doppler shift in this
scenario.

> At very high velocities this is not the case anymore, because the path 
> of the heard wave gets curved.

Nonsense.

Now, let us try to figure out what goes on with the OPTICAL
transverse Doppler effect at relativistic speeds.

1) Let us take a space ship "s" traveling at relativistic
speed: 
-------e--s---------- 
----------|---------- 
----------|---------- 
----------|---------- 
----------|---------- 
----------|---------- 
----------o---------- 

What is the transverse Doppler shift of the emitted light
"e" when the space ship is *geometrically* at its closest
point to the you?

2) Given the same space ship "s" traveling at relativistic
speed: 
----------e--s------- 
----------|---------- 
----------|---------- 
----------|---------- 
----------|---------- 
----------|---------- 
----------o---------- 

What is the transverse Doppler shift of the emitted
light "e" when you *see* the space ship at its closest
point?

3) You are standing at the center of a circular track 
and a space ship is driving around you at relativistic 
speed. Is the light that you see from the space ship
Doppler shifted and if so, is it blue shifted or red 
shifted?

4) You driving a space ship at relativistic speed around
a star following a perfect circular path. Is the light that
you see from the star Doppler shifted and if so, is it 
blue shifted or red shifted?

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#589349

Am 05.08.2022 um 12:29 schrieb Prokaryotic Capase Homolog:
> On Friday, August 5, 2022 at 12:08:33 AM UTC-5, Thomas Heger wrote:
>> Am 04.08.2022 um 09:05 schrieb Prokaryotic Capase Homolog:
>>>
>>> 1) Let us take a race car "r" traveling at Mach 0.2.
>>> 2) You, the observer "o", are standing one mile from the road.
>> No, I'm sitting twenty meters away from the track.
>>> 3) Sound travels 5 sec from the road to your ears at its closest point.
>>> 4) As the car crosses your path, you do not hear sound from where
>>> the car is NOW, but from where it was about 5 seconds ago "e".
>> I'm not a bat and cannot see by the ears.
>> Actually I see light and use my eyes for that purpose.
>
> You do not hear with your ears. Stay on topic.

I have always thought, that my ears are used for this purpose.


>
>> The delay for the finite speed of light needed to be considered, even if
>> very small.
>
> For sonic transverse Doppler shift, it makes hardly any difference.
>
> For optical transverse Doppler shift, it is a different story.

Why?

Fast signals are also signals with finite speed.

It is this finite speed, what causes the Doppler effect and not the 
nature of the waves.

So, why make a distinction between light and sound?


>> But in this example it is totally irelevant, because the track does not
>> move and determins, where the race-car can go.
>>> 5) The sound that you hear from "e" is Doppler shifted to a higher tone.
>>>
>>> -------e--r----------
>>> ----------|----------
>>> ----------|----------
>>> ----------|----------
>>> ----------|----------
>>> ----------|----------
>>> ----------o----------
>
> In summary, whether the race car is *geometrically* at its
> closest point, or one *sees* the race car at its closest
> point, the overall effect is the same: One hears the sound
> of the race car Doppler-shifted to higher notes.
>
>>> Let us try two more scenarios:
>>> 1) You are standing at the center of a circular track and a race car
>>> is driving around you at high speed. Is the sound that you hear
>>> Doppler shifted and if so, is it to a higher or lower tone?
>> I would prefer a linear track.
>>
>> The tone is higher on the side of the approach und lower on the receding
>> side, where the car drives away.
>
> CIRCULAR track!!! At no point does the race car have any
> longitudinal motion with respect to you at the center.
> At race car speeds, one measures no significant sonic
> Doppler shift.


Sure, circular track are a possibility.

But the SRT setting does not contain anything similar to a circular race 
track, but is restricted to streight lateral motion.

So, a simple street would be a better analog than a circular track.

>>> 2) You are driving a race car around a circular track with a loudspeaker
>>> at the center. Is the sound that you hear Doppler shifted and if so,
>>> is it to a higher or lower tone?
>> No, I would always hear the same frequency, because the distance is the
>> important part and does not change in this example, if the speeds are
>> moderatly low.
>
> Finally, you get one correct. At ordinary race car speeds,
> one measures no significant sonic Doppler shift in this
> scenario.


No!

SONIC Doppler frequency shift is, of course, omnipresent in motor-sports.
...


TH

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