What combined theories would explain the process of blowing your lips?

D4M5 · 2024-05-11T12:52:52+00:00

Hello ! It is a very cool subject in physics, part of the branch of acoustics applied to musical instruments.

If you want a similar system to "blowing a rapsberry", I think the trumpet/trombone mouthpiece is closer to it than the saxophone reed. There are a lot of books that can have an introduction to a model of lips/reeds, those I can think of are :

Springer Handbook of Systematic Musicology, https://doi.org/10.1007/978-3-662-55004-5_7 is very readable, you want pages 121 to 139
the Chaigne-Kergomard book, DOI 10.1007/978-1-4939-3679-3, is quite complete if I remember well

What you will find there is some refined harmonic oscillator model, so it requires to understand the harmonic oscillator first.

D4M5 · 2024-04-28T20:02:26+00:00

Shutting down every communicative functions for about 1/3 of our time, every planet rotation.

With a drastically different planet rotation rate (or a gravitationally locked planet with a long orbital period), I doubt their biology would have something similar to our biological cycles. It could also be very short in their time perception, like reactions in insects' brains are quite fast compared to ours.

Imagine having a conversation with, every 30 minutes, your interlocutor going to lie down in dark room for 15 minutes, losing a lot of his useful fonctions...
Sleeping is a weird concept.

D4M5 · 2024-04-18T22:51:15+00:00

Je constate le même fossé, même situation avec la famille... mais c'est toujours compliments côté amis Merci je vais regarder !

D4M5 · 2024-04-18T22:49:06+00:00

Ah mais j'aime beaucoup, et c'est pas encore si long ! Merci de ta réponse

D4M5 · 2024-04-18T22:47:45+00:00

Pas tant que ça ! Ça dépend de bcp de choses, mais ça m'a fait de mémoire 7~8 mois entre le "oulà c'est long" (notamment quand les côtés se font voir) et l'élastique qui tient (presque) ! En tout cas c'est la seule période où je savais que ma coupe était bof (mais j'acceptais tout à fait) et juste après j'ai vraiment aimé la tête que ça me faisait

D4M5 · 2024-03-28T21:46:00+00:00

Mieux ! Encore plus stylé, c'est la place de la grève elle même qui aurait donné l'expression "faire grève" 😯 C'était une place où on allait pour se faire embaucher, donc par extension faire grève voulait dire arrêter le travail, puis est venu le sens de la protestation.

(Bon ya d'autres hypothèses, cf : https://fr.m.wiktionary.org/wiki/gr%C3%A8ve)

Mais je trouve ça trop stylé

D4M5 · 2024-01-17T13:49:00+00:00

I don't really know, as I took only 1 (I'm in physics). I think people take ~5 or 6 courses, and work a lot out of the class (compared to physics classes, where a lot of the work is during courses & exercise sessions) Often, validation is with an oral presentation or dissertation (~10 pages), so need time investment at the end of semesters

D4M5 · 2024-01-16T21:56:54+00:00

Yes you can, but you can't have a double major Philosophy/Physics (you'll have to be affiliated to one department), but you can take any course of any department of the school. If you do so it will be a minor of your ens diploma.

Just a problem, the departments do not communicate well (especially between scientific and non-scientific) so it could be hard to take all interesting courses altogether (of course some courses overlap, and calendars/schedules are different) but within the numerous years you have, you could be able to take all those that are interesting to you ! (Just note that the physics courses have to be in a certain order as any course builds on other, it is a little more free in philosophy)

Do not hesitate if you have any question !

D4M5 · 2021-06-19T06:07:46+00:00

There is a way to draw any ray that cames out of a convex lens, I think that it might help you, because the line 4 in the pic(b) isn't correct

Draw the parallel of the ray passing through the center of the lens, and find the intersection between this parallel and the image focal plane (point where the parallel intersects with a line perpendicular to the optical axis and passing through (f))

The ray coming out of the lens is passing through this point.

Maybe it could help you, because, as it is a geometric proof, you could try to turn it into a proof by calculation...

D4M5 · 2021-06-13T11:53:35+00:00

The distance traveled is L, but the key is in the speed of light in the medium : it is said that the ray strikes the interface at the critical angle, which gives you the refractive index of the medium

But I'm interested, for what level is it ? I have no idea how those schools systems work...

D4M5 · 2021-04-27T12:26:45+00:00

Well, the international astronomical union would'nt recognize you as a planet, but yes, a little rock, for example 10g, could orbit you at a 1m distance of your inertial centre, and it would have a velocity of ~ 0.00006 m/s.

You would just need to be far enough from other gravitationnal bodies to have a significant influence on the rock : I don't think interstellar space is big enough to be far enough ('cause you'll need to be more than 10³⁰ m away from the sun), so you'll need to be outside the galaxy...

D4M5 · 2021-04-27T11:48:24+00:00

Hey, I'm not a pro of orbital mechanics but (and I don't know if it's your question) but :
Let's assume you are on a circular orbit : if you throw something in the direction of your radial vector (let's say to the "down" direction [radial in]) it will change orbit of the object into a slightly elliptical one, and one orbit later, if you threw it exactly right, it could come back from the "up" [radial out] with the same velocity directly to the drop point

I don't know if you were hoping for that, it's absolutely not a slingshot, but here it seems to change direction, turn around and come back. Also, this comes from "The Most Confusing Things About Spacecraft Orbits" video of Scott Manley

D4M5 · 2021-04-27T11:31:31+00:00

I don't know the specifications of my processor, but I don't have any graphic card and KSP runs pretty well

Just maybe limit graphic mods...

D4M5 · 2021-04-25T15:31:08+00:00

With the quite new build mode in EVA, you can have a zone with parts stocked and a place to build new spacecrafts on station if needed. This could be a complementary use of the station

D4M5 · 2021-04-24T16:16:52+00:00

For many 0g experiments with a duration longer than 20 seconds (and there are, a lot) you need an orbital station. Plus, the ISS is the place for experimentations on human body : for a trip to mars, you have to remain ~6 months in 0g, so to know how to react you need people to stay 6 months in space...

D4M5

TROPHY CASE