File talk:RubensTubeLambda.png
that is two wavelengths... -- 24.60.117.113 (Talk) on 2007-8-18
I had the same impression as 24.60.117.113. So, either the flames are higher at both the nodes and anti-nodes (as the first few sentences of this section would indicate), or the graphic is wrong. If the graphic is correct, the nodes and anti-nodes should be labeled.
Furthermore, it is not clear what the "648 mm" is measuring. -- Phyzome is Tim McCormack 00:59, 23 December 2007 (UTC)
Yes, λ has two wavelengths at the image. 62.64.104.210 (talk) 14:08, 10 February 2009 (UTC)
Why two wavelengths? Read on ...
[edit]Okay, I removed the "note this image is wrong" bit. The image is not wrong, and here's the reason.
1) There is a standing wave of pressure in the tube. It has nodes, and antinodes. At the antinodes, the pressure fluxtuates maximally over time. At the nodes, it does not fluctuate.
2) The antinodes correspond to small flames, for at these points the pressure oscillations cause dampening of the fire. At the nodes, where pressure is constant, the flames are large.
3) At a given point of time, One antinode may have maximal pressure. The next node has its usual constant pressure, and the next antinode has minimal pressure. However, a wavelength is between two points of high pressure. Thus, it is between NEXT-NEAREST, rather than nearest antinodes.
As a result, one wavelength is the distance between next-nearest peaks in the flame pattern.