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Swimming As Easy In Syrup As In Water
chthonicdaemon writes "Nature is running a story about scientists at the University of Minnesota who proved that swimming speed is not a large function of the viscosity of the liquid. To do this, they thickened the water in a pool with guar gum. Fun ensued. This is the type of thing that usually keeps to thought experiments. Interesting to see someone prove it."
How about having sex in the stuff?
How come I can't swim in air?
any magazine/newpaper/website that publishes a story like this without photo's should have their ministry of information publishing permit revoked.
Because that is not actually true. The article seems to describe the experiment fairly well, but the underlying theory quite poorly. If objects (or swimmers) were simply launched into the fluid, the difference would be much more obvious. The key point in the experiment is that you gain about the same amount propelling yourself as you lose due to greater drag for the limited range of viscosities investigated (very high or low viscosity could produce different results).
It gives you an idea of how they setup the experement.
The team devised a Rube Goldberg-like contraption using a large green plastic garbage can, a drill with a mixing head, and a length of PVC piping. The device permitted them to pump the guar gum solution directly into the pool, an operation that took about four hours on a Saturday afternoon.
Both are actually the same question. Your body is not structured to "swim" in air. Swiming in air is what we call flying. In all cases forward motion is derived by using force to put stuff that was in front of you, behind you, and the reaction is you going forward.
You are not designed to "float" or "fly" in material as lightly viscous as our atmosphere. The relative density between us, and our lack of a structure designed to produce lift are working against us.
That's not to say that you can't go a long way towards solving this problem. The suits some skydivers use, with pannels betwen their legs, and from legs to arms, allow them to glide a lot further, and have a different perceived terminal velocity than skydivers without these pannels.
Our largest failing is that we do not have a wishbone to hang the necesary musculature on for us to convert our arms to wings. This is true even if our bones were filled with air rather than marrow. (side effect, unless the marrow is given a new portion of the body to reside in, our immune system would have some serious issues.)
-Rusty
You never know...
The mechanics of Natalie Portman locomotion in thermally elevated, coarsely-ground, boiled maize.
It is an even worse analogy than that. The cause of the resistance is not the flat face of the surface, but the flat back of the surface causing turbulance, and drag.
Put a cone on the back of whatever you are trying to push through the air, and the resistance will be significantly lower.
-Rusty
You never know...
' "The best swimmer should have the body of a snake and the arms of a gorilla."
Edward Cussler
University of Minnesota '
TROGDOR!?!?
This is a false rumor spread by that Canadian-grandmother-turned-sex-therapist who has the womens' network show (which is hilarious, incidentally. Trust me.) Ask YOUR doctor about any advice you see on the show before you put it to practice ("I saw it on TV, it must be true!"), okay?
People have been having sex for centuries in the water- lakes, ponds, rivers, oceans, hot tubs, pools, jacuzis, showers, bathtubs- you name it, people have had sex there- and there's simply no evidence of all these injuries you claim(death? Infertility? Riight. I've even seen people claim women could get air embolisms!) A UK women's scuba newsletter asked women divers about their experiences, and surprise- nobody had an injuries.
If anyone who is actually qualified to speak on this subject can present ANY case evidence of this happening in substantial numbers(linkage, please!), I'll shut up- but I think the parent poster is full of nonsense and these "dangers" are about as "dangerous" statistically as catching, and dying from, West Nile Disease- if at all.