Two opposing waves combine to form a standing wave. For waves of equal amplitude traveling in opposing directions, there is on average no net propagation of energy. Moving medium As an example of the first type, under certain meteorological conditions standing waves form in the atmosphere in the lee of mountain ranges. Such waves are often exploited by glider pilots. Standing waves and hydraulic jumps also form on fast flowing river rapids and tidal currents such as the Saltstraumen maelstrom. Opposing waves In practice, losses in the transmission line and other components mean that a perfect reflection and a pure standing wave are never achieved. Another example is standing waves in the open ocean formed by waves with the same wave period moving in opposite directions. Mathematical description In one dimension, two waves with the same frequency, wavelength and amplitude traveling in opposite directions will interfere and produce a standing wave or stationary wave. and
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Scalar energyIf either of the major scalar weapon armed countries e.g. U.S. or Russia were to fire a nuclear missile to attack each other, this may possibly not even reach the target because the missile could be destroyed with scalar technology before it even left its place or origin. The knowledge via radio waves that it was about to be fired could be eavesdropped and the target could be destroyed in the bunker, fired at from space by satellite. Alternatively, invisible moving barriers and globes made of plasma (produced by crossed scalar beams) could destroy any nuclear missile easily while it moves towards the target and failing all these, it could be destroyed by entering the target's territory by passing through a Tesla shield which would explode anything entering its airspace. To begin with, defense using scalar technology could intercept it before it even landed. Tesla globes could also activate a missile's nuclear warhead en route by creating a violent low order nuclear explosion.
Optics on the WebLinks to optics-related applets, tutorials and web sites of interest. NOTE: Some applets no longer work with the most recent Java. If possible, try running on an earlier version. In some cases, I've found alternate applets that are similar and that will run on most browsers (I use Chrome, Safari and Firefox). If you find a link that doesn't work, please email me. Applications of Optics in Communications (Fiber Optics), Manufacturing, Medicine (including the eye) and More Societies, Organizations and Online Magazines This site contains a huge collection of tutorials and applets covering most of an introductory optics course. This is an optics tutorial for chemistry students. optics tutorial with an ophthalmic slant, including how corrective lenses work
The Physics ClassroomLes ondes stationnaires d'IvanovVous trouverez ci-dessous une expérience très intéressante. Elle montre toutes les propriétés des "ondes d'Ivanov" en un seul jet. Puisque la matière est faite d'ondes stationnaires, une telle expérience s'imposait. Standing_Waves_06_Doppler.mkv Je vous rappelle que vous pouvez télécharger les programmes que j'ai écrits dans le but de produire ces séquences en les repérant dans l'un des répertoires ci-dessous, que j'ai rendus publics. Programmes Programs Vidéos Il s'agit véritablement d'une expérience puisque j'ai eu recours au médium virtuel Delmotte-Marcotte pour obtenir l'effet Doppler. Faut-il rappeler que la matière présente manifestement des propriétés ondulatoires et que Louis de Broglie a parlé d'ondes stationnaires? L'origine du facteur de contraction de Lorentz. On sait que la fameuse "aberration" dont parle abondamment Henri Poincaré, qui fut le fer de lance de la théorie de Lorentz, est une découverte de Michelson bien antérieure à 1887. Ci-dessous, M. Un hommage à M.
Interference (wave propagation)Swimming Pool Interference Interference of waves from two point sources. Magnified-image of coloured interference-pattern in soap-film. The black "holes" are areas where the film is very thin and there is a nearly total destructive interference. Consider, for example, what happens when two identical stones are dropped into a still pool of water at different locations. Geometrical arrangement for two plane wave interference Interference fringes in overlapping plane waves A simple form of interference pattern is obtained if two plane waves of the same frequency intersect at an angle. It can be seen that the two waves are in phase when and are half a cycle out of phase when Constructive interference occurs when the waves are in phase, and destructive interference when they are half a cycle out of phase. and df is known as the fringe spacing. The fringes are observed wherever the two waves overlap and the fringe spacing is uniform throughout. A point source produces a spherical wave. for to where
String theoryString theory was first studied in the late 1960s as a theory of the strong nuclear force before being abandoned in favor of the theory of quantum chromodynamics. Subsequently, it was realized that the very properties that made string theory unsuitable as a theory of nuclear physics made it a promising candidate for a quantum theory of gravity. Five consistent versions of string theory were developed until it was realized in the mid-1990s that they were different limits of a conjectured single 11-dimensional theory now known as M-theory. Many theoretical physicists, including Stephen Hawking, Edward Witten and Juan Maldacena, believe that string theory is a step towards the correct fundamental description of nature: it accommodates a consistent combination of quantum field theory and general relativity, agrees with insights in quantum gravity (such as the holographic principle and black hole thermodynamics) and has passed many non-trivial checks of its internal consistency.
Jeune chercheur déçuBonjour Blazingstar, "Pour moi, plus aucun doutes, que depuis 1 siècles, les déouvertes de TESLA sont bien gardées" ---> la question est de savoir, si c'est pour un ambitieux secret égocentrique, ou pour nous proteger de mauvaises utilisations! Rappelle toi la petite expérience de Tesla dans son labo qui a provoqué un tremblement de terre sur 15 km, et ce seulement en s'accordant a la fréquence de résonance de la terre! Néanmoins furent gardées, car on a accès a tout ses brevets. "La gravitation et directement liée à l'énergie du vide" ---> OUI! "Les Nazis avaient de très bonnes sources sur cette énergie du vide, il reste quelques traces de leur station d'essais, deplus la loi de déclassification met à jour certains témoignage assez concordant." ---> outre les origines empiriques babyloniens et indiens, il serait interressant, de se renseigner sur l'origine de leurs connaissances théoriques, par exemple les travaux de l'allemand Hehm. ---> en effet. A bientôt
Numerical apertureThe numerical aperture with respect to a point P depends on the half-angle θ of the maximum cone of light that can enter or exit the lens. General optics In most areas of optics, and especially in microscopy, the numerical aperture of an optical system such as an objective lens is defined by is constant across an interface. In air, the angular aperture of the lens is approximately twice this value (within the paraxial approximation). In microscopy, NA is important because it indicates the resolving power of a lens. Numerical aperture is used to define the "pit size" in optical disc formats. Numerical aperture versus f-number Numerical aperture is not typically used in photography. , which is defined as the ratio of the focal length to the diameter of the entrance pupil: This ratio is related to the image-space numerical aperture when the lens is focused at infinity. Based on the diagram at the right, the image-space numerical aperture of the lens is: thus , and not where
Quantum informationIn physics and computer science, quantum information is information that is held in the state of a quantum system. Quantum information is the basic entity that is studied in the growing field of quantum information theory, and manipulated using the engineering techniques of quantum information processing. Much like classical information can be processed with digital computers, transmitted from place to place, manipulated with algorithms, and analyzed with the mathematics of computer science, so also analogous concepts apply to quantum information. Quantum information Quantum information differs strongly from classical information, epitomized by the bit, in many striking and unfamiliar ways. Among these are the following: A unit of quantum information is the qubit. The study of all of the above topics and differences comprises quantum information theory. Quantum information theory How is information stored in a state of a quantum system? Journals See also