Transcript lift. - PEER

The Forces on an Airplane
Four Main Forces
Lift, Weight, Thrust, and Drag
Weight, Lift, Thrust, Drag
Lift
Thrust
Drag
Weight
Lift
Weight
Thrust
overcomes
is
isofagenerated
force
the
downward
by
is the
directed
toward
caused
on the
the
airplane.
by
center
ofPaper
the
and
The
force
drag
isthat
caused
by engines
air force
resistance,
and
is weight
affected
by Earth.
the
The
gravity.
airplanes
magnitude
don’t
is generated
of
have
the
continuous
weight
by the
depends
wings
thrust,
and
so
the
the
they
mass
forward
fall
oftoall
the
the
shape
andLift
velocity
of
the
aircraft.
Would
aon
box
shaped
airplane
have
a large
or the
small
drag
force?
How
doon
you
know?
airplane
motion
ground.
ofparts,
For
the
airplane.
fuel,
plane
andto
any
move
payload
forward,
board.
the
thrust
A major
forceproblem
in
must
flying
beis
greater
trying than
to overcome
the forceweight.
made by
This
drag.
is done by lift.
Forces Affect Each Other
• Forces acting in the same or opposite
directions have an affect on one another.
• Thrust is used to overcome drag, while lift
overcomes the weight of the aircraft.
Can This Plane Fly?
Lift = 5,000 Newtons
Weight = 8,000 Newtons
Would this plane be able to fly?
Raise your hand!
How Do They Fly?
• The design of the wing (an airfoil) causes air
over the wing to move faster than the air under
the wing. This creates a high pressure system
under the wing. This is Bernoulli’s Principle!
• The high pressure underneath the wing creates
lift. What direction is the lift force in?
Remember
this?
Bernoulli’s Principle
• The toilet paper unrolled because of
Bernoulli’s Principle. Air moves very fast
over the top of the toilet paper, creating a
high pressure system under the paper,
allowing it to move forward and stay level.
This guy LOVES
Bernoulli’s Principle!
Different Types of Airplanes
Amphibian Airplanes
Planes made for stealth
bombing by the military
Airplanes made for speed
Paper airplanes
Paper Airplanes
• Now, you get to make a paper airplane.
• Try and make one with a design that will
allow maximum flight time and distance!
• If you throw it in the
classroom, you will not be
allowed to participate. We
will just be building them
today.