Rubans+Tube

Alyssa Hinz **__Rubens Tube__** The Rubens' tube, also known as the Standing wave flame tube, or simply flame tube, is a physics experiment demonstrating a standing wave. It shows the relationship between sound waves and sound pressure. A length of pipe is perforated along the top and sealed at both ends - one seal is attached to a small speaker or frequency generator, the other to a supply of a flammable gas (propane tank). The pipe is filled with the gas, and the gas leaking from the perforations is lit. If a suitable constant frequency is used, a standing wave can form within the tube. When the speaker is turned on, the standing wave will create points with oscillating (higher and lower) pressure and points with constant pressure (pressure nodes) along the tube. Where there is oscillating pressure due to the sound waves, less gas will escape from the perforations in the tube, and the flames will be lower at those points. At the pressure nodes, the flames are higher. At the end of the tube gas molecule velocity is zero and oscillating pressure is maximal, thus low flames are observed. It is possible to determine the wavelength from the flame minima and maxima by simply measuring with a ruler. Heinrich Rubens was a German physicist born in 1865. Though he allegedly worked with better remembered physicists such as Max Planck at the University of Berlin on some of the ground work for quantum physicists, he is best known for his flame tube, which was demonstrated in 1905. This original Rubens' Tube was a four meter section of pipe with 200 holes spaced evenly along its length. When the ends are sealed and a flammable gas is pumped into the device the building pressure will have only one route to equalize. The escaping gas can be lit to form a row of roughly even flames. Upon introduction of a loud speaker to one of the sealed ends, standing waveforms can be seen in the flames. Within the Rubens' tube, as soon as gas is ignited generally uniform flames will be seen. This is because there is very little pressure differential between any given area of the space inside the tube. Once sound is applied from one end, pressure will change within the tube. Should the sound be an easily measurable frequency, the wavelength will be visible in the series of flames, with the highest flames being where condensation is occurring and the lowest where rarefaction is occurring. media type="youtube" key="ynqzeIYA7Iw" height="315" width="420" align="center"
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It relates to sound by using sound waves to make it work. [] [|http://www.google.ca/#hl=en&safe=active&q=rubens+tube&tbs=dfn:1&tbo=u&sa=X&ei=1vvZT9KNCIb-9QS_-PXtBQ&ved=0CFoQkQ4&bav=on.2,or.r_gc.r_pw.r_qf.,cf.osb&fp=108504a40a1ab20f&biw=1360&bih=673]
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