This is what happens when you get Grizz and Demostix together and let 'em talk about that new math stuff...:D
Shnick
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which the quick-witted but never-the-less kind among the gentle readership here have not pointed out. The blunder-headed mistake.Quote:
accepting of course the possibility of some blunder-headed mistake along the way
For you see, the slope of the line at 30 degrees is not PI/6, it is of course the length of the opposite side of the triangle over the length of the adjacent side, known in the biz as "tangent". Substituting tan(PI/6) in the equations where once PI/6 stood as an object lesson in the wisdom of not posting hastily, and re-doing the calculations gives the ratio of interest as....wait for it....
0.83 with some other digits that aren't 33333, but I'm doing numerical integration here, and probably more to the point, the parabola ain't a catenary curve.
someone 'round here good at Mathematica?
So, then, 83% is all about mathematical relationships, and only coincidentally about comfort?;)
This is off topic, but since there are quants involved I thought you might enjoy this one. We need to add hammocks to the picture though, otherwise it remains only tangentially relevant.
https://lh4.googleusercontent.com/-n...ay-physics.jpg
Got this one from Google+. Look Grizz -- virtual trees! ;)
Hennessy's original suspension hang angle did not include the 30* below horizontal. In fact his orginal directions were to hang the hammock tightly strung. It wasn't until a few years ago that he changed his stuff sack directions to even approximate the 30* angle. There was a lot of confusion a while back when noobies would follow the stuff sack directions and complain they were not comfortable. When they followed the suggestion to loosen the suspension hang they discovered how comfortable a HH can be.
The 83.3 ratio is a starting place. That's all it is not carved in stone.
Its funny, you would think a starting point would be an even or non specific number like 80% rather than 83.3%.
Yep, but the SRL shortens the hammock to about 83% of its length as a starting point (which makes the hammock hang as close to a 30 degree angle as possible with the materials involved). It doesn't do it perfectly, since--even with dyneema line as the SRL--it's a dynamically changing surface with different load points. It's elastic to a certain extent, which is why hanging the hammock looser feels better (if my high-school-level understanding of the physics involved is right).
If my own experience is any guide, the center of the hammock still remains at that 30 degree sag when strung tight. However, the edges of the hammock try to meet each other to take up the rest of the slack--I think this might be due to the way the hammock is whipped--causing shoulder squeeze. Of course, that could just be a body issue on my part; not everyone is built the same way, after all.
Bolded for emphasis. That's the worst pun I've read all month. By rights, I should flee screaming into the night, holding my nose... :lol: