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Airspeed Velocity Of An Unladen Swallow
An anonymous reader writes "Finally, the question is answered: What is the airspeed velocity of an unladen swallow? A designer with too much time on his hands uses his new method for graphically representing Strouhal numbers to clarify a truly pressing question for all armchair zoologists (and a few Monty Python fans)."
just so you know
European actually, and the airspeed velocity of an unladen European Swallow is roughly 11 meters per second, or 24 miles an hour.
Verdict is still out on African(but is probably about the same). The eternal question still stands.
The key to the enjoyment of pop music is to replace any instance of "love" with "C.H.U.D."
The relevant pieces in the script :
A swallow carrying a coconut? and The Bridge of Death
siener's youtube channel
To imply similarity, make the graph larger than it needs to be. Then all of your points will fall in a narrow range and appear closer together.
For this and other presentation crocks, read How to Lie with Charts, and its fore-runners, How to Lie with Statistics and How to Lie with Maps.
The author of the webpage uses far too much verbiage and pretty pictures and doesn't seem to understand what's happening.
Amplitude of wing stroke times frequency of wing stroke is (half) the vertical speed of the wing tip. Forward speed is obviously the horizontal speed. Hence the ratio is dimensionless, and measures how steep (on average) the strokes are. It's not too surprising that these ratios should fall in a relatively narrow range, and the authors of the Nature article say as much. Concretely, if the ratio were, say, 100, the wing would be flapping up and down furiously without advancing much -- if the ratio were 1/100, the wing would hardly be moving.
Sorry, but English modals follow the same pattern for negation:
....l
Will, will not.
Would, would not.
Do, do not.
May, may not.
Must, must not.
Can, can not.
Sure, 'cannot' is a (more) acceptable alternative spelling for that particular case, but not the only acceptable one.
see:
http://www.bartleby.com/68/4/1104.html
http://www.wsu.edu:8080/~brians/errors/cannot.htm
Very good.
In other words, in airscrew terms, the effective pitch of the blade* rpm is a very linear function of speed.
Everyone who did physics at school will know that the optimum speed for a momentum transfer device (eg a waterwheel) is a very simple ratio of the stream velocity.
Damn, I thought it was a pretty neat article, now you tell me it is a (very pretty) statement of the bleeding obvious.
I find your ideas intriguing and I wish to subscribe to your newsletter.
A) you can divide the distance traveled by the swallow by the time it took to travel that distance, or
B) you can use a radar gun to measure speed directly
(Especially when, if you read the article, there is mention that "wind tunnel tests" of swallows showed that their estimates were off (espeically on beat frequency). And they actually used speed measurements to validate their model. Hrm. Seems like an awful lot of work to me...)
My apologies. I'm a bit cynical this morning.
"There are a dozen opinions on a matter until you know the truth. Then there is only one." - CS Lewis (paraprhase)
I did a little scouring around and did find this article:
s /8jonah.html.
http://www.grmi.org/renewal/Richard_Riss/evidence
One of the interesting facts is that there are several documented cases of people swallowed alive by whales who lived to tell the story; and yes, there are historical documents according to the article that support this story, one of which is cited as being from the Babylonian historian Berosus.
Am I a hipster-doofus?
Yeah, they'd need to be made out of metal for radar guns to work. You know, like baseballs, tennis balls, and hockey pucks are all now made out of steel.
Don't blame me; I'm never given mod points.