“what is the airspeed
velocity of an unladen sparrow?”
To begin with, I needed basic kinematic data on African and European swallow
species.
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South African Swallow
(Hirundo spilodera)
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European Swallow
(Hirundo rustica)
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Although 47 of the 74 worldwide swallow species are found in Africa, only two species are named after the continent:
the West African Swallow (Hirundo domicella) and the South African
Swallow (Hirundo spilodera), also known as the South African Cave
Swallow.
Since the range of the South African Swallow extends only as far north as Zaire, I felt
fairly confident that this was the non-migratory African species referred to in
previous discussions of the comparative and cooperative weight-bearing
capabilities of African and European swallows.
Kinematic data for both African species was difficult to find, but the Barn
or European Swallow (Hirundo rustica) has been studied intensively, and
kinematic data for that species was readily available.
Because wing beat frequency and wing amplitude both scale with body mass,
and flight kinematic data is available for at least 22 other bird species, it
should be possible to estimate the frequency (f ) and amplitude (A) of
the European Swallow by a comparison with similar species. With those two
numbers, it will be possible to estimate airspeed (U).
Airspeed can be predicted using a
published formula. By inverting this midpoint Strouhal ratio of 0.3 (fA/U
≈ 0.3) shows that as a rule of thumb, the speed of a flying animal is roughly 3
times frequency times amplitude (U ≈ 3fA).
We now need only plug in the numbers:
U ≈ 3fA
f ≈ 15 (beats per second)
A ≈ 0.22 (meters per beat)
U ≈ 3*15*0.22 ≈ 9.9
... to estimate that the airspeed velocity of an unladen European Swallow is
10 meters per second.
“how much wood could a woodchuck chuck if a
woodchuck could chuck wood?”
If the wood chuck is Chuck Norris then all of it
"what do you think REALLY happened to jfk?"
he faked it
"o michael. ive got something i want answered. if a turkey is sitting
there and bill engvall came and walked by him and told him his joke and
getting tampons for his daughter, what do you think the turkey would do?"
Peck his eyes out
"and second do you think it's possible that the da vinci code could possibly be right if you weren't a christian like you are?"
No

"If a chicken had lips, could it whistle?"
some could and some couldnt just like people
"do you have a thousand dollars I can borrow?"
No
enjoy these other pictures

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