Guy King wrote:

The message
from John Rumm contains these words:


Any other explanations you can think of?


Change of speed of sound in the fluid. That should affect the resonance
much as breathing helium affects the pitch of your voice.

Yup - that could certainly be the case... you would probably expect to
detect a pitch change with temperature as well then as the density of
the liquid changes.

Rotation of the fluid in the container. Particularly if the fluid is

The other problem with rotation based theorys is that I tend to stir
side to side rather than by inducing rotation. You still get the same
effect.

What would really help would be having a name for the phenomenon to make
it easier to find other research.

Perhaps there is a PhD thesis waiting to be had here ;-)


--
Cheers,

John.

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