Arny Krueger wrote:

"Bob Cain" wrote in message


Bob Cain wrote:



Arny Krueger wrote:



Sorry Bob, but I'm not buying.


How about this, then:

1) It is the bulk velocity, the flow of air, at the rest position
that propagates out as the velocity wave.


Frankly, over my head.

That's hard to believe. What part of it evades you?



2) The bulk velocity at the rest position is the same as the surface
velocity of the piston.


Frankly, over my head.

Same.



And, finally:


3) In the frame of reference of the rest position of the
piston, no Doppler shift can be observed.


That seems wrong, because the following is right:

In the frame of reference of the piston, no Doppler shift can be observed.

If you are in the frame of reference of the piston, you're
going to get shanken _all_ to hell. :-)


Bob
--

"Things should be described as simply as possible, but no
simpler."

A. Einstein