Can an airplane on a conveyor belt take off? (resolved)

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Ahmed
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Re: Can a plane on a treadmill take off? (resolved)




by Ahmed » 15/05/21, 13:07

... it is said that the conveyor belt compensates for the advancement of the plane, that's all!

Precisely, it does not compensate for anything at all since the wheels-carpet assembly does not constitute the right reference point and only "smears" you with errors ... : Wink:
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Re: Can a plane on a treadmill take off? (resolved)




by Christophe » 15/05/21, 18:04

Frankly, I stop debating with such bad faith! I thought you were more open-minded than that! : Evil: : Evil: : Evil:

The error is you who is inside and well and on 2 points: if you neglect the friction of the wheels then the lift cannot exist! So you are making a double mistake!

I proposed a compromise solution that should have satisfied you intellectually...

Spin a Boeing wheel at 1 rpm ... we'll see if the power of its internal friction is not counted in MW ... : Cheesy:
If 1 Million RPM is not enough for you goes to 100 M ... OSEF since there is no limit in the statement!

There's nothing worse than a donkey who doesn't want to move forward!
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Re: Can a plane on a treadmill take off? (resolved)




by Ahmed » 16/05/21, 09:50

If we calmly resume and admit the statement, the plane will accelerate and the carpet too (at speeds not possible!) And the plane will take off. More, if we assume that the belt prevents speeding up from the ground (for no other reason than is what the one who wrote this glue claims!), then the plane will stay where it is ... : Mrgreen: It is this last assumption (underlined) which is absurd ... : roll:

Imagine an irresistible force that meets an indestructible obstacle, what do you think will happen? 8)
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Re: Can a plane on a treadmill take off? (resolved)




by Christophe » 16/05/21, 12:40

Oh cow that's it !!

Image

It is absurd for two reasons:

a) A conveyor belt can stop a plane in a world with friction but it is technologically impractical given the different orders of magnitude

b) A conveyor belt cannot stop an airplane in a frictionless world but in a frictionless world there is no lift so planes either

But a statement must be accepted! Physically and mathematically this problem is not absurd and is very interesting: the proof that we spent dozens of messages and cumulative hours there! : Cheesy:

Ahmed wrote:Imagine an irresistible force that meets an indestructible obstacle, what do you think will happen?


Let's not talk about my sex life in public! : Mrgreen:
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Ahmed
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Re: Can a plane on a treadmill take off? (resolved)




by Ahmed » 16/05/21, 16:43

Sorry, Christophe, I was not aware of being indiscreet! : Oops: : Oops: : Oops: : Oops:
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Re: Can a plane on a treadmill take off? (resolved)




by Obamot » 16/05/21, 20:01

Him and his forum, it boils down to that

D28E4DF1-5BCF-4EF8-BC26-EE867A8CE15F.gif
D28E4DF1-5BCF-4EF8-BC26-EE867A8CE15F.gif (87.17 Kio) Consulté 2585 fois
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Re: Can a plane on a treadmill take off? (resolved)




by Christophe » 06/02/24, 18:49

Ahmed wrote:If we calmly resume and admit the statement, the plane will accelerate and the carpet too (at speeds not possible!) And the plane will take off. More, if we assume that the belt prevents speeding up from the ground (for no other reason than is what the one who wrote this glue claims!), then the plane will stay where it is ... : Mrgreen: It is this last assumption (underlined) which is absurd ... : roll:

Imagine an irresistible force that meets an indestructible obstacle, what do you think will happen? 8)


Almost 3 years later...I'm doing it again...because it's the period of knots in the brain (and who here likes that... : Mrgreen: )

I rephrase the solution:

The correct solution is for the plane to take off (almost) as if nothing had happened. because a treadmill of an airplane on wheels (which cancel the friction on the ground, therefore on the carpet, at uh like "100-X" %) cannot prevent this plane from moving forward because it transmits its power by pressing on the air and not via its wheels...the X% will slightly slow down the plane which will take a little more distance to take off...

Think of a bike on a treadmill: push it by hand on the frame, it will move forward almost as if nothing had happened (with friction X near the wheels). It's the same here.

If the power was transmitted by the wheels, like almost all land vehicles, it would be different... the same with a plane that brakes (wheels locked), on skis or without wheels...

The statement is therefore based on an unrealistic, misleading and twisted hypothesis...but that has already been said!
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Re: Can a plane on a treadmill take off? (resolved)




by Remundo » 06/02/24, 21:41

the plane takes off if the relative wind on its wings generates lift greater than its weight.

the treadmill under the wheels can do whatever it wants. If the plane puts its engines on full throttle, it will gain forward speed and the wheels will follow the relative movement between the carpet and the movement of the plane.

everything else is just smoke and mirrors. :P
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Re: Can a plane on a treadmill take off? (resolved)




by Christophe » 06/02/24, 21:46

Let's not rekindle the controversy...on this subject. There were injuries at the time see above…

It is not a question of reactor power but of the application of forces: a 500 gram scale model will also take off...since it relies on the air and not on the rolling road...

Basically the treadmill has no effect on a moving plane, that is to say whose wheels are turning (see the bicycle) except that of the friction of its wheels… (a pouillema)
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