WILL IT FLY?

>>8550805
yes it will fly

the treadmill literally can't do shit to stop the plane, the plane's wheels are frictionless thus the tread mill no matter how fast it spins cannot stop the forward thrust of the plane's turbines

>>8550823
But here's the thing, the plane needs the wheels to roll on in order to gain it's velocity but it's always counteracted by the belt

>>8550805
The question is ambiguous, and possibly nonsensical. The question presumes that the running belt is holding the plane stationary, but provides no mechanism for that to actually happen. Probably the safest "realistic" answer is yes, the plane can take off and the belt will simply spin up the wheels, though that breaks the "exactly match the speed of the wheels" part of the question.

>>8550837
The wheels are frictionless, the wheels do not power the plane, only the turbines. It wouldn't matter if the plane was on sleds

you didn't read a thing I said

>>8550805

No, heavier than air flight is impossible.

>>8550843
>though that breaks the "exactly match the speed of the wheels" part of the question.
Maybe the belt starts off not moving, then accelerates as the plane does?

>>8550846
technically, if the plane so much as accelerates, the tread mill will immediately attempt to counter the plane's velocity which its impossible to and the treadmill and wheels will accelerate into infinity

>>8550837
unlike cars, planes don't get any thrust from their wheels.

>>8550846
>Maybe the belt starts off not moving, then accelerates as the plane does?
That wouldn't matter. The belt can't stop the plane from moving forward, so it can't run at the same speed as the wheels.

>>8550805
It will take off right after the wheels start sliding/explode from the treadmill rolling too fast

If it could dont you think it would be incorporated onto aircraft carriers? Instead of a ramp
>>8550823

>planes can take off while stationary
Ya ok

>>8550864
>>planes can take off while stationary
except its not stationary

the plane will move forward until it reaches its take off speed for which it will just take off

the plane either rolls off the conveyor belt or takes off, depending on how large the belt is

the wheels have nothing to do with anything, they're red herrings

>>8550856
No shite but they need the wheels to get moving or else they would scrape their undercarriage

>>8550883
the wheels do not "get them moving" they're there ONLY to roll on, they're frictionless

>>8550874
No the belt will match the speed of the wheels. Have you ever ran on a treadmill? You dont go anywhere

>>8550895
>No the belt will match the speed of the wheels. Have you ever ran on a treadmill? You dont go anywhere
The wheels do not provide thrust for the plane

what force counter acts the force of the turbines?

>>8550896
It doesnt matter what provides thrust, if you get rollarblades and attach a rocket to your back and stand on a treadmill you will not move forward.

>>8550900
Yes it does

Theres only one source of thrust in this equation, the wheels provide no resistance, nothing

>>8550837
No it doesnt, the plane could drag the wheel forward

>>8550900
>stand on a treadmill you will not move forward.
yes you will, assuming the rollerblades are frictionless you certainly would

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>>8550805
>747
> is NOT powered by the Wheels! !!!!
Jet Engines push / pull AIR

>>8550895
>>8550900
>It doesnt matter what provides thrust
The morons have arrived.

>>8550903
So if a hamster runs on a wheel fast enough it will move forward?

You all are retarded. The wheels are a red herring. It's the air moving over the wings that matter. Either the wings can move through the air and create lift like an airplane taking off. Or the air can pass over the wings like a in wind turbine.
Like a

>>8550913
No because unlike a jet, a hamster doesn't move the air with a fucking turbine engine

>>8550915
Then why do planes have to move to take off?

>>8550917
So air can run over their wings.

Unlike you or a hamster that relies on your legs for propulsion. A jet's method of propulsion does not rely in gripping the ground to shoot itself forward. It uses a turbine to push itself forward. The wheels do NOTHING, they could be sleds or skates, unless some equal and opposite force goes against the turbines the plane WILL move forward

>>8550912
They are right though, retard. Most of people in this thread is missing the point of the question, the conveyor belt thing is in the question to let us assume that the plane WILL NOT MOVE. If the plane doesn't move forward it can't fly. This board is full of autistic retards that can't even comprehend the nature of a simple question like this.

OP HERE, WHY ARE WE ASSUMIG THE WHEELS ARE FRICTIONLESS?!?!? THIS IS SUPPOSED TO BE A REAL SITUATION

>>8550845
kek'd

>>8550961
>Most of people in this thread is missing the point of the question, the conveyor belt thing is in the question to let us assume that the plane WILL NOT MOVE.
>This board is full of autistic retards that can't even comprehend the nature of a simple question like this.
If you actually read any of the posts in this thread, or any of its predecessors, you would understand people's objection to that part of the question.
Yes, the question assumes the plane won't be able to move forwards. However, the justification given for that assumption is nonsense - spinning the wheels won't keep the plane from accelerating, and therefore the claim "the conveyor belt is designed to exactly match the speed of the wheels" is unreconcilable.

>>8550977
>WHY ARE WE ASSUMIG THE WHEELS ARE FRICTIONLESS
Because if we start including factors like friction, the question simply becomes "what breaks first", and that's not terribly interesting.

>>8550844
Wheels aren't frictionless.

>>8551020
Exactly, meaning that the turbines depend on the wheels in order to translate the thrust into forward motion. But this forward motion would be counteracted by the conveyor belt which would prevent any lift from being generated

Wheel bearings will be turning at twice the design speed, that is the only difference.

>>8551020
they're virtually frictionless

a 747 puts out 50k pounds of thrust PER engine

the wheels might generate a few hundred pounds of friction resistance.

>>8551026
>the turbines depend on the wheels
NO THE WHEELS APPLY NO POWER

REPLACE THE WHEELS WITH SKATES OR SLEDS you stupid shit

the turbines apply a force

what force goes against the plane to stop it from accelerating?

the treadmill applies zero force to the plane because the wheels are (virtually) frictionless

>>8551026
>the wheels provide thrust
mo they don't the wheels don't do anything they're free spinning

>>8551044
SUCK OFF, THE THRUST MOVES THE PLANE WHICH MOVES THE WHEELS AND THE WHEELS ROLL THE PLANE ALONG ITS PATH BUT IF THE WHEELS ARE BEING ROLLED BACK BY THE BELT HEN IT CANT MOVE FORWARD

>>8551046
Yes I get that, but the rolling friction is what allows the plane to progress forward but the treadmill keeps it back

>>8551068
THE WHEELS ARE FREELY MOVING AS LONG AS THE BRAKES AREN'T BEING APPLIED YOU FAGGOT

>>8551073
FAGBAG MILLIONAIRE! THE PLANE NEED THE ROLLING FRICTION TO ROLL FORWARD WHICH GETS COUNTERACTED BY THE BELT

>>8551071
The treadmill applies no force on the plane

Velocity is scalar force is a vector

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>>8551084
>velocity is scalar
Are you retarded?

>>8551086
>says the retard who thinks he can counter act a force with a velocity

The planes thrust is in the engines the wheels have nothing to do with it.

The treadmill has no way to apply an opposing force on the engines

>>8551093
The thrust causes a force which causes a velocity but this velocity is counteracted by the belt.
Me - 1
Dumb cunt anon - 0

>>8551094
You can't counter act a "velocoty" the wheels can spin as fast as they can and nothing is opposing the thrust of the engines

Friction like brakes on the wheels causes a force that would slow down the plane the wheels are free spinning and virtually frictionless

The Velocity of the plane isn't even measured by the wheel speed

The plane is completely separate from the treadmill

The treadmill going in reverse wouldn't accelerate the plane any faster

>>8550805
Thank you OP. This thread is wonderful.

>>8551094
>causes a Velocity

Shit I didn't know force = mass * velocity

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>>8551097
Me - 0
Smart cunt anon - all of em

I got it like 5 posts ago I'm just being a diva roach.

Thanks anons, turns out I was wrong but I'll take my loss in return for newly gained basic physics knowledge.

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>>8551081
if only the wheels could affect the thrust of a plane how would even it move after leaving the ground

>>8551112
Bu...bu...but
Muh friction

>>8550805
This is a very small problem
Nested in a big problem with lots of messy things to get you mixed up and confused. Essentially the only thing that matters is the forces acting on the wheel. As the turbines produce forward thrust the axel moves foreward applying a leftward force to the wheel. The wheel experiences this force and wants to move leftward but as it is in contact with the surface it also experiences a force of static friction at the point in which the wheel contacts the treadmill. Due to the low coefficient of friction between the axel and the wheel and the high coefficient of friction between the wheel and the surface instead of sliding on the surface the wheel rotates around the axel. As it rotates it experiences some amount of static
Friction, but this quickly becomes kinetic friction. As the wheel rotates the surface moves in congress with it changing its relative state of motion. Since the plane is only moving forward relative to the treadmill and not the air around it the plane experiences essentially no air resistance (and thus no lift). As thrust increases the treadmill increases its speed such that it matches the rotation of the wheel. At that point we're fine, but the turbines are shooting matter out the back increasing its velocity relative to the atmosphere. This will continue up until the point at which the forward thrust produced by the turbines overcomes the maximum static friction in the wheels. At which point it does not matter how quickly you spin the treadmill. The plane will move forward.

Imagine applying the brakes to the wheels as the thrust increases. What happens? Well the turbines continue to increase forward thrust and the treadmill keeps spinning faster all the same, but once that maximim force of friction acting on the wheels is overcome the plane will move forward dragging the wheels against the treadmill. This will happen whether the wheels are spinning or not.

>>8550805
yes, the wheels are not connected to the driveshaft. It will roll along the treadmill, because the velocity relative to a point on the treadmill is not what matters. It's the velocity relative to the air. Relative to a point on the treadmill (at least while that point is moving to the right), it will take of at 2*takeoff speed.

As written the plane cannot take off.
Why? Chose your answer:
1) In order to meet the restrictions of the scenario the plane cannot move using its engines, period. Any movement produced by its engines would violate the setup.
2) If by some miracle the plane has a non-zero wheel speed, by the setup the conveyor belt exactly matches but in the opposite direction and thus there cannot be any non-zero airspeed.

Not following the setup as presented is not acceptable in any meaningful discussion.

>>8551327
The real answer is that the question was either made by an inbred mongoloid who doesn't know how a planes work, or by a troll, and in either case shouldn't be discussed at all

Changing the definition of a plane just to stoop down to the retardation of the question is foolish and pointless

>>8551341
At last I see the light.

>>8550914
This, since no air is providing the necessary lift the plane will never take off.

>>8551341
I sincerely enjoy that someone took the time to make this. Thanks for sharing bud.

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>>8550805

Yes OP, it will fly.

Think about it in the following way:

When an airplane moves on a runway, it's essentially following a one dimensional coordinate system. A number line, if you will. As x increases, the plane gets closer to take off.

In this scenario, the same thing holds, except that the coordinate system is the treadmill, and it loops around. That doesn't matter though, because the plane is still progressing longitudinally, and its wheels are rolling, so it will take off, guaranteed.

>>8550912
You have fallen victim to a masterful ruse

the fun begins when the first tire bursts

>>8550914
This is the only correct answer in this thread, I can't believe sci is this retarded

>>8550985
>However, the justification given for that assumption is nonsense - spinning the wheels won't keep the plane from accelerating

Dude, the conveyor belt is there to set the constraint [math]r \dot{\theta}=v[/math] where [math]\dot{\theta}[/math] is the planes wheels angular velocity and v the speed of the conveyor belt. Once this constraint is set true, it doesn't matter where the thrust comes from, it doesn't matter how fast the wheels spin, the plane will not move forward, hence it will not take off.

>>8550805
no because the wings will not gain any lift. when you run on a tread mill there isn't any wind resistance to push you back, this is the same reason why it will not take off.

>>8550805

Reference planes (lol pun!)

If it was a car that had thrust through its wheels connected to the conveyor belt - no it wouldn't move, just like a runner on a treadmill.

But the thrust is delivered to the air from the planes engines - so no connection to the belt, the plane will move.

>>8550805
No, because the plane will remain stationary relative to the air around it, and thus will achieve no lift.

>>8550837

It's not a car, the forward thrust is not provided by a drive-train connected to the wheels.

In this situation, the rolling friction of the planes wheels is different than the static friction (assuming no slip) of the driven wheels ona drive-train.

With the plane's engines thrusting it forward and the conveyor belt moving at the same speed in an opposite direction, the wheels will have an angular velocity/acceleration that is double that of a plane taking off on a runway.

The real catch here is whether or not the bearings in the plane's wheels can handle the heat/deformation of double the expected rotational force.

>>8550837
This. The acceleration of the belt (and corresponding angular acceleration of the wheels) would have to be ABSOLUTELY INSANE to produce enough friction to counteract thrust and fulfill the described criterium, but as long as that criterium is fulfilled the plane cannot move.
>>8550844
>The wheels are frictionless
Not in reality. I'm not talking the minuscule rolling friction either - spinning the wheels up in RPM requires friction from the belt (or some other input). In theory, with enough power and strong enough equipment, the belt could hold the plane in place against it's own thrust at least for a brief moment, before accelerating beyond the speed rating of the tires and blowing everything up.

The other possibility is that the plane spools up the engines, and the treadmill TRIES to hold it in place but still FAILS to do what it's "designed to" do. In this case, the plane would then be able to move (despite the treadmill's best efforts) and take off.

>>8551608
But that's wrong, faggot, and if you knew how to do a free body diagram you would know why.

All that happens with your magi-fucking-conveyor belt is that the wheels spin like mother fuckers.

What happens if you drop the plane from a great height, and turn on the engines at the same time? Assume the plane falls evenly reminaing on its belly, and neglect air-resistance from the downward motion.

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>>8550805
You motherfuckers are retarded talkin bout fuckin wheel friction n shit. The plane will not take off BECAUSE of the treadmill. It keeps the plane stationery, so the aerodynamically structured vehicle cannot use the AIR to achieve liftoff. The plane must achieve a minimum speed through an atmosphere to get off the fucking ground, otherwise you are blowing up a treadmill trying to hold back 4 jet engines playing a winning battle of tug-o-war

>>8550852
what if you put some kind of controller that damped the response of the treadmill to the plane's wheels?

>>8551368
Airplane on a treadmill is an extremely old engineering troll. I've even heard that it's been posted on Fidonet, so there's a chance that this image is older than the average 4chan poster.

>>8551803
You are retarded to think a Velocity is on par with a force

What force counter acts the thrust of the engines?

>>8551811
Its a bullshit problem that implies overwhelmingly unrealistic friction will counter the forward thrust of the plane. If there is no risk of tire failure, then heat and friction will hold it in place and the plane never moves. You motherfuckers are a meme

>>8551811
Its is stated the treadmill keeps the plane in place (((somehow))) so it doesn't matter if it would actually work, thats irrelevant. Cheat physics man

If the air hostess serves coffee fast enough to counter the planes forward motion, will it still be able to take off?

The question is nonsense.

>>8550805
No, the bearings in the wheel would explode under normal loading and double velocity.

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>>8551783
Wow faggot, you're so fucking right. I'm a dumb piece of shit, sorry. I thought if the treadmill speeds matched with the planes wheels it wouldn't be able to move. Is there still hope for me in physics? This is now an academic failure thread.

>>8551339
So, why are you here discussing it?

The definition of a plane has not been changed.

You must be a real boring person in person.

>>8550805
The real answer is yes

The actual answer, ie, the one that the one who asked the question is looking for, depends
Usually you can find out what they want you to "realize" in a simple dialogue

>Will it take off
>Yes
>But it's stationary
>Oh, you're right, No
It's just an appeal to their intelligence

>>8550805
747 is not a rocket, and must have air moving across its wings in order to fly. At first, the belt would prevent this from happening, so lift would not occur.

>>8550844
Even if the wheels were frictionless, flight is achieved through airpressure which is not being generated by a non moving wing. The best you could argue with frictionless wheels is that the lack of friction implies the plane's already flying.

How fast would a treadmill need to be spinning backwards in order to hold the plane in position through the minor friction inherent in the planes wheels?

>>8553386
The answer to the question is NO.
The plane cannot attempt a takeoff as the belt cannot prevent it from taking off if it attempts to take off.
If the plane attempts to take off one of the conditions cannot be met: the conveyor belt is designed to exactly match the speed of the wheels, moving in the opposite direction.

baka, of course the plane can take off.
if the plane has a take of velocity of x m/s
the wheels will feel and apparent 2x m/s
however the conveyor belt cannot stop the aircraft from producing trust and therefore lift.
the conveyor only interacts with the wheels, which aren't powered in anyway.
Think about this, can a plane fly over a moving conveyor belt when its wheels aren't touching it, of course it can. The same applies for taking off on a conveyor as well.

>>8553662
the problem is you can't prevent the plane from moving. the wheels really don't matter. especially if the wheels were frictionless, the plane's just going to move forward unhindered, and then take off

>>8550805
this was literally on mythbusters faggots

>>8550805
It takes off.
https://www.youtube.com/watch?v=YORCk1BN7QY
https://www.youtube.com/watch?v=4owlyCOzDiE

>>8550805
Energy analysis using classical mechanics. The thrust energy of the plane's turbine is the input, the forward motion of the plane is the output.

[math]u(t)=\frac{1}{2}m\dot{x}^2+\frac{1}{2}J\dot{\theta}^2[/math]

, where m is the mass of the plane, x is the position of the plane, theta is the relative angular position of the plane's wheel, and J is the moment of inertia of the plane's wheel. Assume the wheel does not slip on the contact between the wheel and the runway. Taking the runway's speed to be equal to the wheel speed,

[math]\dot{x_2}=r\dot{\theta}[/math]

, where x2 is the relative x-position of a fixed point on the runway and r is the radius of the wheel. However, the rotation is also related to the velocity x of the airplane in relation to the velocity of x2. That is, when the plane moves forward, the wheel's actual rotation speed depends on the difference in speed between the plane and the runway.

[math]r\dot\theta=\dot{x}-\dot{x_2}[/math]

Setting both x and x2 as positive toward the right and theta as positive toward the counterclockwise direction, it can be seen by intuition that when velocity x is greater than velocity x2, theta has a negative velocity, negating the above equation to this one:

[math]r\dot\theta=\dot{x_2}-\dot{x}[/math]

In conjunction with the first theta-x2 relation, this necessitates that the x-velocity is equal to zero. Therefore:

[math]u(t)=\frac{1}{2}J\dot{\frac{x_2}{r}}^2[/math]

That is to say that in a classical force analysis, all the energy goes into the rotation of the wheel. When the plane tries to move forward, the wheel will rotate to accommodate not just its new speed, but also its new kinetic energy, which necessarily negates the plane's forward thrust entirely. Gyroscopic action screws this one in a classical analysis.

>>8556126
The speed of the wheels here was obviously not the same as the speed of the conveyor. The wheel's speed was the speed of the conveyor PLUS the speed of the airplane.

Energy analysis using classical mechanics. The thrust energy of the plane's turbine is the input, the forward motion of the plane is the output.

[math]u(t)=\frac{1}{2}m\dot{x}^2+\frac{1}{2}J\dot{\theta}^2[/math]

, where m is the mass of the plane, x is the position of the plane, theta is the relative angular position of the plane's wheel, and J is the moment of inertia of the plane's wheel. Assume the wheel does not slip on the contact between the wheel and the runway. Taking the runway's speed to be equal to the wheel speed,

[math]\dot{x_2}=r\dot{\theta}[/math]

, where x2 is the relative x-position of a fixed point on the runway and r is the radius of the wheel. However, the rotation is also related to the velocity x of the air plane in relation to the velocity of x2. That is, when the plane moves forward, the wheel′s actual rotation speed depends on the difference in speed between the plane and the runway.

[math]r\dot{\theta}=\dot{x}-\dot{x_2}[/math]

Setting both x and x2 as positive toward the right and theta as positive toward the counterclockwise direction, it can be seen by intuition that when velocity x is greater than velocity x2, theta has a negative velocity, negating the above equation to this one:

[math]r\dot{\theta}=\dot{x_2}-\dot{x}[/math]

In conjunction with the first theta-x2 relation, this necessitates that the x-velocity is equal to zero. Therefore:

[math]\frac{1}{2}J\dot{\frac{x_2}{r}}^2[/math]

That is to say that in a classical force analysis, all the energy goes into the rotation of the wheel. When the plane tries to move forward, the wheel will rotate to accommodate not just its new speed, but also its new kinetic energy, which necessarily negates the plane's forward thrust entirely. Gyroscopic action screws this one in a classical analysis.

>>8556126
The speed of the wheels here was obviously not the same as the speed of the conveyor. The wheel's speed was the speed of the conveyor PLUS the speed of the airplane. Hail memescience.

>>8556220
>>8556229
Guess it just doesn't want to take that closing math tag. Enjoy your wider browser ¯\_(ツ)_/¯

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>>8556220
Well done sir.

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>This thread is still alive

>>8556126
These alleged simulations visibly fail to match the problem description.

>>8556266
Of course they do. As everyone else in this thread has pointed out, the problems description is incoherent.

The plane won't take off.

It uses engines to move and the wheels are his legs.

Therefore even at maximum thrust, his wheels will be locked in place? Therefore the plane won't gain momentum.

>>8551341
my fooking sides

It takes off with the wheels rotating at twice the speed of a normal take-off.

t. engineering professor

>>8557612
You fail to adhere to the given instructions, go hang yourself.

>>8557916
The given instructions are incoherent, there's no way to discuss this problem without breaking them.

Think of the treadmill requirements:

Jack up the plan by the wings and then put it on jackstands with wheels. Now position you best treadmill design under the elevated 747 wheels and try to move everything. It might move, but not with enough force that a gentle push wouldn't overcome it. The engines provide far more than a gentle push.

>>8557916
>the wheels are spinning faster than usual
does not negate the notion that the conveyor belt is matching the rate of rotation of the speed, you fucking mong.

Here's a hint: The turbines on a 747 are not unlike a rocket or a ramjet. What the fuck do wheels care if they spin a little faster or slower? They're not actually applying any force to the plane unless the brakes are engaged.

>>8557934
The instructions are comprehensible and clear.

The answer has been given several times.
If you are incapable or reading and recognizing said answer in no way means the question is incoherent.

There are several variations of this question that get used, many of which cannot be answered realistically without breaking the conditions. The particular version being discussed as presented in the OP has a simple answer which makes most of the ongoing discussions unnecessary.

>>8550805
thanks for posting this again. I just read through the comments to get another good laugh at the expense of the moron brainlets embarrassing themselves.

I think once a week this should be a mandatory thread on a regular schedule for my amusement.

>>8558004
Yes, it does negate the notion and you cannot change that fact without changing the problem.

If you can't follow the ONE AND ONLY constraint what is the point of you attempting to engage in a meaningful discussion?

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>>8558004
For a force analysis, picture the plane moving forward. The conveyor accommodates that motion by moving the plane back, and it does so via gravity enacting static friction on the wheels, friction that moves it backward. We assume that for some amount of time, the plane is still on the runway while it's moving. This means that, for some amount of time, the motion of the wheels corresponds to the speed of the plane, or rather, the speed of the plane with respect to the moving conveyor.

Now, imagine that the thrust turns off before the plane can take off. When you remove the force of the thrust while the conveyor is still moving, which way does the plane accelerate? What do the forces look like when you remove the thrust? Is it really just the thrust force acting on the plane, or is there something else?

Draw a free-body diagram, and explain your answer.

>>8558030
>>8558040
Why do you assume that the wheels are powered?
They are not powered.
They do not apply force onto the plane. The plane cannot apply force to the wheels, other than gravity keeping it tied to the ground.

The rotation of the wheels is a natural reaction of gravity bearing down on the wheels, and friction with the earth, caused by the plane moving forward.

The only applicators of force the plane is allowed to affect, are the turbines and the control surfaces. The wheels are not even part of the equation. This stupid setup is no different from the plane already being in the air.

Your shitty explanation hinges on the idea that a plane is the same as a car. Which it fucking isn't. The wheels are a freely rotating element and have nothing to do with the motions of the plane.

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>>8550844
>The wheels are frictionless
In which retards think that the only way the wheels can transfer energy and momentum to the plane is via friction.

>>8558048
Take the thruster force away while the conveyor is moving backward, and which way does the plane move? Could there be some force acting on the plane that isn't the thruster?

No one said that the wheels were powered. It's a simple question that a high schooler could get right without a second thought.

>>8558048
>They do not apply force onto the plane.
Apart from the somewhat ambiguous problem description and physical implausibility of the conditions, this is the crux of the matter.

Recall landing in a plane. You might have noticed that when the wheels hit the ground there is a backward jolt to the plane. This is a transfer of momentum from the ground to the plane via the wheels.

This happens because the wheels can transfer momentum to the plane via the axle, even in the absence of friction. To the extent that the wheel pushes exactly backwards on the axle, it pushes the plane backwards. No friction is required.

>>8558073
>backward jolt to the plane
Not just an upwards jolt.

>>8558073
Because planes land with the brakes you numbscull.

>>8558048
You are mixing two different people in your linked replies.

In regards to my reply that you linked, I have never stated anything remotely close to the wheels being powered.

The wheels are a very important part of the setup, in fact they are a key part, one single constraint of the problem.
The setup is fundamentally different that a plane already being in the air.

In the given problem the wheels are key to the motion of the plane, they have everything to do with the motion of the plane.

>>8558073
>I don't know what brakes are

>>8550892
But the wheels are absolutely REQUIRED to spin to get the plane moving, how else could you take off?? You have never flung on a plane arent u?

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>>8551084
>Velocity is scalar force

>>8559042
is the ground is slippery enough you can lock the brakes and 'slide' into the air.
Also, water and snow landings. Pontoons and skis.

>>8557539

Aeroplane wheels don't have engines to provide forward momentum.

>>8559047
Sounds like a missed opportunity.
Quickly, to the Patent office!

>>8550805
First off? Really dude?! Come on, what does it take for a plane to take off? You need the plane to be moving so that the wings experience a drag and lift force. Second, even if the wheels and track were moving at the same speed what would happen if you removed the track? Would it go anywhere? No, because the plane itself isnt even moving.

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>>8559045
>velocity is a force

IF the treadmill is long enough for the standard takeoff, so it doesn't trip & fall essentially, which is a funny thought

then all the wheels do is spin freely at takeoff speed + speed of treadmill. the relative low friction of the bearings means nothing above the wheels even notices

because, after all, it would take an INCREDIBLE IDIOT to think that the wheels move the plane forward.

now, a car on the treadmill would move at speed of wheels - speed of treadmill, because the wheels are what provide it's forward motion.

the plane would take off in exactly the same distance as off the treadmill. the only possible scenario where the is wouldn't happen is if the treadmill was moving many thousands of miles per hour, which could maybe melt the bearings

>>8550805
I came here wondering what a science board on 4chan would be like. Boy did I get exactly what I expected. What a gaggle of fucktards you all are.

This is an isolated system. If the plane cannot move forward, it cannot get any air beneath it's wings, which means no drag.

>>8550805
Will not take off, because there is not relative movement with the air, and is it what causes the lift efect

>>8559358
why can't it move forward? the wheels don't drive the plane forward. they just freewheel while the engines push it. what does it matter to the wheels if they move at a couple more miles an hour on top of the hundreds at which they spin during takeoff?

>>8559358
To clarify further, if the treadmill constantly adjusts to oppose the wheels exactly, that is the same thing as the wheels not existing at all. OP is essentially asking if a plane standing still can take off. Any retard can answer that question.

>>8559390

riddle me this: if the wheels are what drive a plane forward, why the fuck does it have jet engines?

the wheels spin freely. doesn't matter at what speed.

>>8559388
You are joking right? It doesn't matter what causes the wheels to move forward. What matters is that when they do move forward the treadmill matches their rolling speed in reverse. The cause of the wheels rolling forward is irrelevant. The plane cannot move on a treadmill that always opposes it's motion. A plane that cant move cant lift.

>>8559391
>>8559392
Referred to this response. Not much of a riddle really man.

>>8559392
>>8559395

https://youtu.be/01Q83yxdDaI
https://youtu.be/YORCk1BN7QY

it's already been done.

i'll ask again: why do airplanes have propellers if the wheels matter?

>>8550805
>I'm in the discussion of my life against this one slapnut.
tell us which side of the discussion you are on so we can call you a fucking retard if you deserve it

protip: the lift under the wings is not related to the angular momentum of the wheels

>>8550805
Here's a factoid that iwll blow your mind

If a plane is at a complete standstill, with the brakes engaged, but sitting on top of an aircraft carrier, if the carrier drives fast enough, the plane will lift into the air

>>8559399
These videos actually prove what I'm saying. This plane, despite the conveyor belt underneath it, manages to still move forward. I am not saying the wheels "matter" the way you keep insisting.

The way the original question was proposed, the plane cannot move forward, because there is a conveyor underneath that perfectly matches the wheels in the opposite direction. If it were possible to create this scenario exactly, the plane would not lift, because it would not be moving. The plane in these videos manages to overtake the conveyor. That's why it takes off.

I will say for a final time, and I am not responding again. If a plane CANNOT MOVE FORWARD, it cannot lift, assuming there isn't a massive wind blowing. This is a fundamental truth of physics. Fuck the wheels. I don't give a shit about the god damn wheels. Without a measurable advance in position, there is not lift.

>>8559418
How the fuck is that supposed to blow anyone's mind?!?! That is exactly the result you should expect! God help us all. This world is doomed.

>>8559420
you're right about lift.

but let's put it another way. you're in rollerskates, on one of those horizontal escalator tracks in airports. you don't skate forward, only coast.

if you hold on to someone, & they walk you forward, you will move at the same speed whether you're on the fast track or not. (they don't get on it)


the wheels spin freely. doesn't matter if they're on the treadmill or not.

>>8559418
>>8559414
please back me up here

>>8559431
Lets not put it another way because it was asked a specific way. This isn't a debate.

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>>8559430
it blows a lot of clowns minds', that's the problem

>>8559431
>if you hold on to someone, & they walk you forward, you will move at the same speed whether you're on the fast track or not. (they don't get on it)
exactly

the "trick" here is that the wheels are not powered by the engine. they spin freely. if the plane was attached to a steel beam, it would stay in the same place and the wheels would just spin at the rate of the conveyor belt's movement

Assuming the wheels will survive any amount of heat and friction it will take off, because the treadmill won't counter the engine thrust. The plane will move forwards while both its landing gear and the treadmill spin at insane speeds.

>>8559390
And yet so many here got the wrong answer...

>/sci/ doesn't know how planes work

>>8559456
So, is the conveyor belt still exactly matching the speed of the speeds but in the opposite direction?
If not, you are not answering the question asked whileusing the information provided.

>>8559031
Typically jets don't use brakes to stop but rather reverse thrust and flaps.

>>8559443
>the "trick" here is that the wheels are not powered by the engine. they spin freely.

They spin freely in terms of friction but energy and angular momentum must be supplied to them to allow them to spin.

So, not 'freely' in those terms.

If the engine thrust start the plane moving forward slightly/infinitesimally then the conveyor will detect this and start to move faster. This will speed up the wheels. The conveyor will, via its friction with the wheels, convey energy and angular momentum to the wheels. It does this by pushing the bottom of the wheel backwards.

So there is a backward impulse to the plane as a whole. The wheel's overall momentum changes in the backward direction. But the wheel is locked to the plane via the axle. So the plane also much be pushed backward. This occurs via the axle via a backwards force *which does not depend on friction in the axle or on wheel brakes.

>>8559042
You are aware that it is possible to fly with skis and pontoons, right?
How else would anyone depart from the ocean?

Suppose you have a roller skates on and and a jetpack on your back. According to the question if the jetpack is pushing you foward at a speed of 10000000 km/h that means that the wheels are also moving at 10000000 km/h. But the question states that the treadmill is moving in the opposite direction relative to the speed of the wheels and therefore it would move at -10000000km/h. Now correct me if I'm wrong, but 10000000km/h + (-10000000km/h) = 0km/h and therefore the average speed would be 0. thus the object would not move