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Hi !

Here is an experiment i created to measure the speed of sound while opening a good bottle of wine !

Cheers !

It works also fine if you make the "pop" with a finger in a test-tube !

https://youtu.be/QYF0bw6l0Ww
Julien, thanks for the useful phyphox code with many images. You have even took into account the end correction 0.61 D !!
Only a photo of the bottle used in the experiment is absent and it is unclear what equation has to be used .

As I understood, you have used the approximation by the \lambda/4 standing wave in a tube closed at one side.
If you have not yet finished the bottle an approximation by the Helmhotz resonator is more appropriate for the next opening.
You're right !
The air column in the bottleneck act as a one-sideclosed pipe resonator. The peak frequency is the one of the quarter wavelength standing wave.

The formula used is :

Cair = 4 f0 (L + 0,61xD)
I was insired by this paper :
https://aapt.scitation.org/doi/10.1119/1.5145480

And of course, once the bottle is open and some wine has been drunk, one can use the formula of the Helmotz resonnator instead ! May be i will add it in a few days !

[attachment=120]
Here is a result with a test tube.
The end correction for a one-side closed pipe is a half of 0.61 D, i.e. 0.3 D ... as in the paper you have cited.
Oups !

Here is the corrected version.
I will have to open a new bottle this evening !!!

[attachment=121]
[attachment=122]
Dear Julien.

For a test tube with L = 23.7 cm and D = 2.8 cm your program gives f = 375.0 Hz and c_air = 381 m/s, to high...
Strange, but the standard "Audio spectrum" of phyphox gives f = 351 Hz (c_air = 345 m/s) - much more acceptable
By the way the resonance peak of our "Resonance curve" gives f = 362 Hz ...

It is very important to measure the temperature around the bottle of wine to be opened. I would suggest to add a feature to your program: determination of the temperature from c_air using a simple formula t = (c_air/20)² - 273 (°C) .

A+

References:

Peter Froehle,  "Finding the Outdoor Temperature Using a Tuning Fork and Resonance",
The Physics Teacher 44, 358 (2006); https://doi.org/10.1119/1.2336137

Jeffrey D. Goldader, "Determining Absolute Zero Using a Tuning Fork",
The Physics Teacher 46, 206 (2008); https://doi.org/10.1119/1.2895669
Thank you for these  interesting articles !

There is some strange behaviour with your test tube indeed !

I try some experiments with mine. I put it in the oven few minutes and i found a frequency of  515.63 Hz for a measured air temperature inside the tube of 65°C. This gives a speed of 370.37 m/s. It seems to be a pretty good result.
Then i tried with the test tube in the freezer for a few minutes. With a measured air température of -5°C i found a frequency of 468.75 Hz. Exactly the same as in the room temperature of about 20°C.
Strange !!!
I had pretty good result by hitting the open end of 250mL graduated cylinder with my open hand ! Less than 5% of error.
[attachment=147]

Here is the video :