# Thread: does shape cause levity

1. ## does shape cause levity

does shape cause levity

def: levity
lift
ant: gravity

def: topspin
the up surface rotating into the headwind

Originally Posted by rwjefferson
unsupported assertions
the shape of the wing is the force that lifts bumblebees and birds and planes
Originally Posted by billvon
The shape of a wing helps create lift, yes. That's easily provable in a wind tunnel.
Levity is already present in verse initial inertial pressure differential. Shape only makes lift more or less efficient. Shape or warp is not the same as force. What is true for space holds true here on earth.

easily provable in a wind tunnel
airplanes can fly upside down
all shapes can provide lift
a sphere with a shiny smooth surface topspinning exhibits lift
rough balls not so much

Name a shape that cannot exhibit lift.
Name the force that lifts shiny topspin.
Name the force that sinks a baseball.

peace
ron

2. Sweep your hand through some smoke. Your hand is quite a good wing shape. Your palm skates across the smoke. Your knuckles throw the smoke up. You are creating a hole of less resistance.. like a little cave. Easier to move up than down. Fill a bath with water, slide your hand through the bath water. The small curvature in your hand causes a vector angle rotation. You can twist your hand to change the rotation angle, you hand can become a rudder.

Vector angles combined with areas of less resistance... that's your answer in the end.

3. This thread belongs in pseudoscience.

4. This thread belongs in the Cesspool.
And the first two posters in this thread with it.

5. Originally Posted by rwjefferson
does shape cause levity

def: levity
lift
No. A difference in pressure, or a redirection of the air flow, or buoyancy, causes lift.

No need for the term "levity", either, if all you mean is "lift".

Levity is already present in verse initial inertial pressure differential.
I can't parse that.

Shape only makes lift more or less efficient.
More efficient than what?

Shape or warp is not the same as force.
Obviously. Otherwise we wouldn't need three words - one would do.

easily provable in a wind tunnel
airplanes can fly upside down
all shapes can provide lift
Explain how a non-rotating sphere can provide lift.

Name the force that lifts shiny topspin.
Topspin tends to sink, not lift. The force is a result of different airflow above and below the ball.

Name the force that sinks a baseball.
Same thing as with tennis.

6. Originally Posted by rwjefferson
does shape cause levity
Certainly:

lev·i·ty
noun \ˈle-və-tē\
1: excessive or unseemly frivolity

Another example: Tim Minchin: Storm
(some language may offend).

7. Levity is already present in verse initial inertial pressure differential.
Originally Posted by James R
I can't parse that.
It is an engineering explanation of laughter.

8. I forgot to add angular momentum to the vector interpretation. So you have a vector angle of momentum, which would be the rudder, or the bend of a wing, or the bend of your hand in bath water, or the spin of the object.

9. Originally Posted by rwjefferson
does shape cause levity
easily provable in a wind tunnel
airplanes can fly upside down
all shapes can provide lift
You do realize that the lift of aiplane flying upside down is completely different than a plane flying right side up.

It is a horribly inefficient way to fly because the lift is provided by the force of the air on the bottom side of the wing giving an upward force which causes a huge amount of drag.

The normal way that a wing works is that the low pressure on top of the wing lifts the entire body with very little drag.

By the way if you want to see how inefficient it is to fly upside down try this experiment - mount the wings upside down on an airplane and try to take off. I highly recommend that you do this by remote control so no one is killed.

10. As Trippy noted, "levity" means "inappropriate lack of seriousness." The use of the word to mean "lightness" is archaic.

11. Originally Posted by origin
You do realize that the lift of aiplane flying upside down is completely different than a plane flying right side up.
Depends on the aircraft! Aerobatic aircraft (like the Extra) have symmetric airfoils that generate lift efficiently in both directions.

12. some may find this site illuminating

http://www.grc.nasa.gov/WWW/K-12/airplane/wrong1.html

a series of incorrect theories of lift.

13. Originally Posted by billvon
Depends on the aircraft! Aerobatic aircraft (like the Extra) have symmetric airfoils that generate lift efficiently in both directions.
Interesting, I did not know that. I assume that there is some way to adjust the wing angle, otherwise there would be no net lift one way or the other, right?

14. Originally Posted by Boris2
some may find this site illuminating

http://www.grc.nasa.gov/WWW/K-12/airplane/wrong1.html

a series of incorrect theories of lift.
Nice little site.

15. I am in good shape, so mine does not cause levity anymore.

16. Originally Posted by origin
Interesting, I did not know that. I assume that there is some way to adjust the wing angle, otherwise there would be no net lift one way or the other, right?
At a zero angle of attack a symmetric airfoil generates no lift, so aerobatic aircraft use one of several methods to get lift:

-Angle of attack change via flight surface trim. Basically you trim the airplane so it always flies nose up, which gives you a greater AOA and more lift.

-Angle of incidence change. You can tilt the entire wing relative to the airplane to give it a positive AOA when the aircraft is level; that does the same thing.

-Flaps (used primarily for landing and low speed flight.) They change the effective AOA of the wing so you can fly level with the nose not raised as much.

17. Originally Posted by billvon
At a zero angle of attack a symmetric airfoil generates no lift, so aerobatic aircraft use one of several methods to get lift:

-Angle of attack change via flight surface trim. Basically you trim the airplane so it always flies nose up, which gives you a greater AOA and more lift.

-Angle of incidence change. You can tilt the entire wing relative to the airplane to give it a positive AOA when the aircraft is level; that does the same thing.

-Flaps (used primarily for landing and low speed flight.) They change the effective AOA of the wing so you can fly level with the nose not raised as much.
Thanks! Interesting stuff.

18. def: bernoulli
fluent flowing faster over a boundary forces lower static pressure
and vice versa
lower pressure over a wing accelerates air mass back and downwards

def: newton
a measure of mass acceleration
action~reaction
equal in verse opposite

def: fluent
all that flows over time
everything

A non rotating sphere "lifts" just like all other shapes and gliders and sizes. Make it as light as possible, launch into an up draft.

incorrect theory of lift
an airfoil lifts at neutral angle of attack

self evident truth
an airfoil lifts at downward angle of airmass departure
airplanes with can lift upside down
all shapes can provide lift
all shapes are subject to stall
soapy spheres exhibit lift without rotation
top spinning bowling balls force airmass downwards
top spinning golf and tennis balls force airmass downunder and upwards in verse fuzzy boundary layer
even wikipedia is behind in publishing the truth

ItS
peace
ron

a wing harnesses a segment of vortex
a vortex is the dance of newton in verse bernoulli

19. Originally Posted by rwjefferson
def: bernoulli
A non rotating sphere "lifts" just like all other shapes and gliders and sizes.
No, it doesn't. A nonrotating sphere does not generate lift.

Make it as light as possible, launch into an up draft.
If it rises it will be due to drag, not lift. (Same reason thermals pick up leaves, grass, petals etc.)

incorrect theory of lift
an airfoil lifts at neutral angle of attack
Some airfoils do indeed generate lift at zero angle of attack.

self evident truth
an airfoil lifts at downward angle of airmass departure
airplanes with can lift upside down
All agreed.

all shapes can provide lift
Incorrect. Some, as mentioned above, cannot.

all shapes are subject to stall
Strictly speaking yes, as turbulent flow can be caused with any shape.

20. dogma dies hard

incorrect theories of lift
lift is the same as minimal drag
a nonmoving wing generates lift

strictly speaking
a wing that forces airmass downwards is in deed attacking the headwind
shape only makes lift/drag more or less efficient
shape only redirects force
redirection is not the same as force
shape is not the same as force

Name a shape that lifts without force.
Name the force that generates lift.

peace
rw

force is inertial pressure differential

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