# Bernoulli`s Principle:

```•When a force is applied to a
confined fluid, the increase in
pressure is transmitted
equally to all parts of the
fluid.
Transmitting Pressure in a Fluid
• When force is applied to a confined fluid,
the change in pressure is transmitted equally
to all parts of the fluid.
Bernoulli’s Principle:
• A Swiss
scientist born
in 1700’s that
is most
famous for his
work in fluid
pressure.
Remember!!!
• Air is a gas and a fluid
• Air pressure is due to the
motion of its particles
• Bernoulli and Pascal
dea1 with PRESSURE!
Bernoulli’s Principle
• Pressure in a moving stream
exerts less pressure than the
air surrounding the moving
stream Quick stream = low air pressure
Slow stream = High air pressure
Standing Tennis Ball
• In your notes,
hypothesize
why the tennis
ball ‘stands’ in
the air.
• Draw the air
currents.
Hi! I’m a
Tennis
Ball
AIR FLOW
• The tennis ball is
surrounded by an air
stream of equal
speed, thus equal
pressure.
• The down force is
Gravity!!
‘G’
AIR FLOW
Bernoulli &amp; Flight
• Bernoulli’s
Principle is what
allows birds and
planes to fly.
• The secret
behind flight is
‘under the
wings.’
•The air on top of the wing must travel a longer
distance than the air below the wing. Therefore,
the air on top of the wing traveling faster = less
air pressure.
Creates Lift
AIR
LIFT
THRUST
DRAG
GRAVITY
•The engines provide THRUST.
•The wings provide LIFT.
•Gravity provides the ‘G force.’
•And, fluid friction provides the
DRAG.
```