Applications of Bernoulli

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Applications of Bernoullis Principle
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DemosPing Pong Ball in funnelPing Pong Ball
in air streamPaperparallel paper
http//www.physics.ucla.edu/demoweb/demomanual/mat
ter_and_thermodynamics/fluids/bernouli_demos.html
Note With demos 1.5 periods
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slower speed
faster speed
more pressure
less pressure
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As the speed of a fluid increases, the pressure
in the fluid decreases.
P a 1/v
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As the speed of a fluid increases, the pressure
in the fluid decreases.
P a 1/v
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Bernoulli Flight

• Bernoullis Principle is what allows birds and
  planes to fly.
• The secret behind flight is under the wings.

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https//www.youtube.com/watch?vO8qCA2mZvVI
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AIRFOIL
On top greater air speed and less air pressure
On bottom less air speed and more air pressure
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v2
v1
Net force on wing?
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LIFT
THRUST
DRAG
GRAVITY
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Spoiler airfoil reversed
less air speed more pressure
greater air speed less pressure
net force downward
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Racecar
Spoiler provides better traction and avoids lift
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Wind over a roof
Patm Proof ½ ?v2
v
proof
v 0 patm
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slow air speed
fast air speed
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Curve Ball
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(No Transcript)
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Golf ball dimples
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Winds over a mountain
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Shower Curtain
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Review Ping pong balls? Cardboard
walls? Paper? Baseball?
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Instability in passing Trailers?
Trains passing each other?
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Atomizer As air passes at top of tube, the
pressure decreases and fluid is drawn up the tube.
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http//www.youtube.com/watch?v5ltjFEei3AIfeature
related
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2009 Darwin Award
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2009 Darwin Award
(15 December 2009, Germany) A U2 subway driver
found a body laying besides the underground
tracks in Berlin. Because there was no video
surveillance camera at that location, it took
police two days to reconstruct what had happened.
Apparently Yasin A., 22, was alone in the subway
car when he decided it would be a brilliant idea
to destroy one of the windows. By swinging feet
forward from a handrail into the window, he not
only managed to burst the glass but also
succeeded in being sucked out of the moving
train, and was left dead on the tracks. He was
alone in the compartment at the time if an
observer had been present, perhaps the young
underground rider would not have engaged in
destructive nonsense that led to his senseless
death.