Adjustments of wingbeat frequency and air speed to air density in free-flying migratory birds
نویسندگان
چکیده
منابع مشابه
Adjustments of wingbeat frequency and air speed to air density in free-flying migratory birds.
Birds adjust their flight behaviour to the physical properties of the air. Lift and drag, the two major properties in aerodynamics, are highly dependent on air density. With decreasing air density drag is reduced and lift per wingbeat decreases. According to flight mechanical theory, wingbeat frequency and air speed should increase with decreasing air density, i.e. increasing flight altitude. A...
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ژورنال
عنوان ژورنال: Journal of Experimental Biology
سال: 2009
ISSN: 1477-9145,0022-0949
DOI: 10.1242/jeb.031435