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Pacer. How does a guitar work? Contents First, something about sound If you put your finger gently on a loudspeaker you will feel it vibrate - if it is playing a low note loudly you can see it moving.

How does a guitar work?

When it moves forwards, it compresses the air next to it, which raises its pressure. Some of this air flows outwards, compressing the next layer of air. The disturbance in the air spreads out as a travelling sound wave. At any point in the air near the source of sound, the molecules are moving backwards and forwards, and the air pressure varies up and down by very small amounts. The strings. Strings, standing waves and harmonics. The animation shows the interaction of two waves, with equal frequency and magnitude, travelling in opposite directions: blue to the right, green to the left.

Strings, standing waves and harmonics

The red line is their sum: the red wave is what happens when the two travelling waves add together (superpose is the technical term). By stopping the animation, you can check that the red wave really is the sum of the two interacting travelling waves. The figure at right is the same diagram represented as a time sequence - time increases from top to bottom. Strong coupling of torsional and transverse waves in a bowed string. This page is an appendix for the scientific paper: Bavu, E., Smith, J. and Wolfe, J.

Strong coupling of torsional and transverse waves in a bowed string

Formulating Science in Terms of Possible and Impossible Tasks. David and I have been working on this together for the past three years, and we’ve been applying it to many different problems.

Formulating Science in Terms of Possible and Impossible Tasks

So far, the two completed parts of our trying out constructor theory to see whether it can solve problems are: a fundamental theory of information within physics1; and the constructor theory of life2, which applies this new theory of information to a fundamental problem that's at the boundary between physics and biology, and has to do with how certain features of living things, such as the ability to self-reproduce very accurately, are compatible with the laws of physics as we know them. In these two cases, you can see how switching to this new mode of explanation allows one to change the perspective and address the problems in a much more effective way. These are two examples where switching to this new mode of explanation makes all the difference. Take information, for example. One question might be how do you test constructor theory? [1] D. Music - Brian Eno’s Reading List: 20 Essential Books for Sustaining Civilization.

By Maria Popova Deconstructing a magnificent mind through his reading diet for intellectual survival.

Brian Eno’s Reading List: 20 Essential Books for Sustaining Civilization

UPDATE: The folks from the Long Now have kindly asked me to contribute to the Manual for Civilization library — here is my own reading list. Tons of Albert Einstein Documents Are Now Online for Free. Einstein Papers Project at Caltech. FLP Vol. I Table of Contents. The Feynman Lectures on Physics Vol. I Ch. 1: Atoms in Motion. 1–1Introduction This two-year course in physics is presented from the point of view that you, the reader, are going to be a physicist.

The Feynman Lectures on Physics Vol. I Ch. 1: Atoms in Motion

This is not necessarily the case of course, but that is what every professor in every subject assumes! Bill Gates Favorite Books. Park East Press Even though Gates can get a meeting with almost anyone, he can't land a sit-down with Norman Borlaug, the late biologist and humanitarian who led the "Green Revolution" — a series of innovations that kept a huge chunk of humanity from starving.

Bill Gates Favorite Books

"Although a lot of people have never heard of Borlaug, he probably saved more lives than anyone else in history," Gates says. "It's estimated that his new seed varieties saved a billion people from starvation," many of whom were in India and Pakistan. Borlaug was awarded the Nobel Peace Prize, the Presidential Medal of Freedom, and the Congressional Gold Medal for his efforts — and is one of only seven people to do so. For Gates, Borlaug is a model in getting important work done in the world. Mozambook - les ebooks de littérature - ebooks of literature. OpenClassrooms, Le Site du Zéro - Les cours les plus ouverts du Web. Graphisme & interactivité blog par Geoffrey Dorne.

World of Mathematics. If we can divide a number A by a number B, without remainder, we say that B is a factor or divisor of A, and that A is a multiple of B.

World of Mathematics

For example, 7 is a factor of 21, 4 is a factor of 20 and 60 is a multiple of 12. When thinking about number problems, it is often useful to find all the factors of a number. To do this, we should note that factors always appear in pairs. For example, 7 × 3 = 21, so 3 and 7 are a factor pair of 21. Let us write down these factor pairs, until we meet in the middle: And these are indeed all the factors of 24.

Some numbers are very special because they only have two factors: 1 and itself.


The Periodic Table of Videos - University of Nottingham. Find Your Name in the Periodic Table of the Elements. Top 10 Scientific Mnemonics. Humans.

Top 10 Scientific Mnemonics

To add up to. Sound Bottle : une bouteille qui remixe les sons aux alentours. Voilà qui va ravir les créateurs musicaux en tout genre : un prototype du nom de Sound Bottle vient d’être présenté et le principe est simple.

Sound Bottle : une bouteille qui remixe les sons aux alentours

Il s’agit d’un petit appareil, qui a la forme d’une bouteille, et qui enregistre les sons aux alentours pour créer une symphonie en les regroupant et en les remixant. Le résultat peut être vraiment bluffant et beau, surtout si vous choisissez bien l’endroit où vous abandonnez votre bouteille et les sons que vous lui faites entendre. Mais jugez plutôt par vous même : Le fonctionnement de l’appareil est donc simple : quand elle est bouchée, Sound Bottle garde en mémoire tous les sons qu’elle capte. 10 techniques de manipulation de l'opinion publique et de la société. Le Petit Érudit.

HowStuffWorks "Learn how Everything Works!".

La boite verte

Université Ouverte des Humanités: Le projet. Créée sous l'impulsion de la Sous-Direction TICE, Service des Technologies et des Systèmes d’Information du Ministère de l’Enseignement supérieur et de la Recherche et du Ministère de l’Education nationale, l’Université Ouverte des Humanités est l' Université Numérique Thématique consacrée aux champs disciplinaires des Sciences humaines , des Sciences sociales , des Lettres , des Langues et des Arts . Pour favoriser une meilleure réussite des étudiants , notamment en licence, et contribuer au développement de l’université numérique française , l’UOH offre sur ce portail accessible gratuitement des contenus pédagogiques validés scientifiquement, pédagogiquement et techniquement : texte, audio, vidéo, multimédia, etc.

TED: Ideas worth spreading. Net Sommaire. De la servitude moderne - le livre. « Mon optimisme est basé sur la certitude que cette civilisation va s’effondrer. Mon pessimisme sur tout ce qu’elle fait pour nous entraîner dans sa chute. »


Béhémoth. Un article de Wikipédia, l'encyclopédie libre. Tour de Babel. Un article de Wikipédia, l'encyclopédie libre. Empire romain. Un article de Wikipédia, l'encyclopédie libre. Cet article traite d'une période de l'histoire de la Rome antique. Belzébuth. Language Exchange Community - Practice Foreign Languages. ¤ Portail des civilisations anciennes. Does Language Influence Culture? Updated July 23, 2010 12:01 a.m. ET (Please see Corrections & Amplifications below.) Do the languages we speak shape the way we think?

Do they merely express thoughts, or do the structures in languages (without our knowledge or consent) shape the very thoughts we wish to express? Take "Humpty Dumpty sat on a... " In Russian, you would have to mark tense and also gender, changing the verb if Mrs. In Turkish, you would have to include in the verb how you acquired this information. Les expressions françaises décortiquées - Accueil. Fractale. Spheres. Spheres [ english | español | portugués ] Spherical Surface of Dialogue Spheres shaped by dialogue, a net of semantical combinations. The richness of words consists in their relations with one another. CALCULATRICE SCIENTIFIQUE EN LIGNE. Share Book Recommendations With Your Friends, Join Book Clubs, Answer Trivia. Ebooks libres et gratuits. Ebooks gratuits - Télécharger des revues et magazines en pdf gratuits.

Free Audio Books - Download an audio book in mp3 or iPod format today! FILMS7 VOD - VIDEOS - CLIPS - BANDES DEMOS COMEDIENNES - VIDEO A LA DEMANDE - FILMS A VOIR EN LIGNE - CINEMA D'AUTEUR. Free Audio Book - Discourse on the Method of Rightly Conducting One’s Reason and of Seeking Truth in the Sciences by René Descartes. By: René Descartes (1596-1650) The Discourse on Method is best known as the source of the famous quotation “cogito ergo sum”, “I think, therefore I am.” …. It is a method which gives a solid platform from which all modern natural sciences could evolve. With this work, the idea of skepticism was revived from the ancients such as Sextus Empiricus and modified to account for a truth that Descartes found to be incontrovertible.

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