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BACKGROUND
Explain to students the Mechanics of Flight via anatomical comparison
Forces of thrust, lift, drag and weight work together to make both
airplanes and birds
fly. If all are equal, then the bird or plane will fly in a level
path.
Thrust is the pull of gravity. The car rolling down a hill faster
and faster is an example
of this pull
Lift is generated when the forward motion through the skies overcomes
its weight. Birds create lift by moving forward. Think of when you've
been at the beach and watched a sea gull or tern running into the
wind to begin flight. The upper air on top of the wing draws the
bird upwards while the increased pressure underneath also pushes
it upwards.
The force that tends to push something along with the flow of the
air is drag. Think of a garbage can or the stones and other debris
that roll down the street in a rainstorm. In a flying bird, drag
is reduced with the shape of the wings and body as well as the angle
of
the wing. To slow down, a bird will use drag by spreading its tail
and lowering its feet.
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