![]() In fact, for a plate of circular shape, resting in the centre (or the border, or at least in a set of points with central symmetry), the nodal vibration modes all have central symmetry, so the observation of Jenny is entirely consistent with well known mathematical properties. He was particularly impressed by an observation that imposing a vocalization in ancient Sanskrit of Om (regarded by Hindus and Buddhists as the sound of creation) the lycopodium powder formed a circle with a centre point, one of the ways in which Om had been represented. According to Jenny, these structures, reminiscent of the mandala and other forms recurring in nature, would be a manifestation of an invisible force field of the vibrational energy that generated it. The sand or other substances were organized into different structures characterized by geometric shapes typical of the frequency of the vibration emitted by the oscillator. Jenny put sand, dust and fluids on a metal plate connected to an oscillator which could produce a broad spectrum of frequencies. In 1967 Hans Jenny, a follower of the anthroposophical doctrine of Rudolf Steiner, published two volumes entitled Kymatic (19), in which, repeating Chladni's experiments, he claimed the existence of a subtle power based on the normal, symmetrical images made by sound waves. The figures thus obtained (with the aid of a violin bow that rubbed perpendicularly along the edge of smooth plates covered with fine sand) are still designated by the name of "Chladni figures". This provided an important contribution to the understanding of acoustic phenomena and the functioning of musical instruments. Įxperiments of this kind, similar to those carried out earlier by Galileo Galilei around 1630 and by Robert Hooke in 1680, were later perfected by Chladni, who introduced them systematically in 1787 in his book Entdeckungen über die Theorie des Klanges (Discoveries on the theory of sound). The normal modes of vibration, and the pattern of nodal lines associated with each of these, are completely determined, for a surface with homogeneous mechanical characteristics, from the geometric shape of the surface and by the way in which the surface is constrained. The points form a pattern of lines, known as "nodal lines of the vibration mode". The powder moves due to the vibration and accumulates progressively in points of the surface corresponding to the sound vibration. The German musician and physicist Ernst Chladni noticed in the eighteenth century that the modes of vibration of a membrane or a plate can be observed by sprinkling the vibrating surface with a fine dust (e.g., lycopodium powder, flour or fine sand). Hooke ran a bow (musical) along the edge of a glass plate covered with flour, and saw the nodal patterns emerge. ![]() ![]() On July 8, 1680, Robert Hooke was able to see the nodal patterns associated with the modes of vibration of glass plates. Other examples include the Chladni Plate and the so-called cymascope. The apparatus employed can be simple, such as the Chinese spouting bowl, in which copper handles are rubbed and cause the copper bottom elements to vibrate. Different patterns emerge in the excitatory medium depending on the geometry of the plate and the driving frequency. Typically the surface of a plate, diaphragm, or membrane is vibrated, and regions of maximum and minimum displacement are made visible in a thin coating of particles, paste, or liquid. The term was coined by Swiss physician Hans Jenny (1904–1972). From the film Inner Worlds Outer Worlds.Ĭymatics (from Ancient Greek: κῦμα, romanized: kŷma, lit.'wave') is a subset of modal vibrational phenomena. Creation of visible patterns on a vibrated plate Resonance made visible with black seeds on a harpsichord soundboard Cornstarch and water solution under the influence of sine wave vibration A demonstration of sand forming cymatic patterns on a metal plate.
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