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by Amnon 5670 days ago
Turns out the page is a reference to a certain Fail Whale -- http://www.whatisfailwhale.info/.

The thing that's bothering me about the fail whale -- all the strings that hold the whale are curved. Is this physically possible? (Assuming the birds can hold the whale in the air). Shouldn't at least one of the strings be a straight line?

6 comments

If a string is hung between two fixed points, then it will fall in the shape of a catenary (hyperbolic cosine):

http://en.wikipedia.org/wiki/Catenary

Even when one of the ends is weighted down rather than fixed, I think it's still going to want to fall into a catenary curve, because that curve minimizes the potential energy of the string itself, and there is some equilibrium between the lower potential energy of the string and the higher potential energy of the object. How far the curvature departs from a straight line is probably a function of the ratio of mass between the lifted object and the string itself. With a whale and some yarn, it's going to asymptotically close to a straight line, but still slightly curved. However, fail whales are apparently light enough to be carried by a handful of birds, so the weight is probably comparable to the string itself.

If the strings have any mass of their own, they will be curved.
Not if their starting point is directly above their ending point and there's no wind...
Their starting point obviously isn't above their ending point, though.

mansr is right, I've been looking at this all wrong because I assumed the weight of the strings was small compared to the weight of the whale. But if the strings are dense they will curve under their own weight. So we're not looking at a super-light whale, we're looking a regular whale supported by super-heavy strings.

(Where do you get strings so dense that the mass of a short stretch is comparable to the mass of a whale? Why, the same place you get those goddamn birds, of course.)

"Turns out"? I'm sorry, isn't it obvious that the page is a cross between the Fail Whale and Moby Dick?
Not if you don't know what the Fail Whale is.
Yes. I can only assume that they're not strings, they're hyperstrong super-thin curved rigid bars.
The whale could be just out of the water and still have some momentum.
Not only that, but air drag on the strings too.