Stolen from another forum

Okay... I'm going to write an essay about this, and this will be the last I f***ing say about it.

The question posed is this:

You have a plane on a treadmill. For the purposes of this assumption, the treadmill is capable of reaching any speed without destruction, as are the wheels on the plane. The treadmill is also of infinite length, so there is no end-limit to the distance the plane can travel before taking off.

Now, this treadmill is designed and has sensors so that it can immediately, with no delay, detect the speed of the plane, and run counter to that speed.

The question posed is this: Will the plane take off?

Now, in order for a plane to take off, it needs to generate lift. In order to generate lift, there must be airflow past the wings. In order for there to be airflow past the wings, the plane must be moving forward. (We are discounting planes with VTOL engines.)

So the question ultimately boils down to this: Will the plane move forward, or will it be kept stationary?

This is answered easily by outlining the forces on the plane, their directions, and their magnitudes.

The engines apply a very large force to the rear of the plane, in the forward direction.

The treadmill applies a contact force to the wheels, of a magnitude equal to the coefficient of friction between the wheels and treadmill, multiplied by the weight of the plane.

If the plane is moving, the air creates a drag force equal to a coefficient multiplied by the square of the plane's velocity. It acts opposite the direction of motion.

We already know that the plane can take off under ordinary circumstances, so obviously the drag is insufficient to prevent the plane from taking off. In fact, we can pretty much disregard it, as it only limits the velocity of the plane (terminal velocity) and this is far greater than the velocity needed to take off.

That leaves the contact force and the engines. Every plane's wheels use a bearing system to allow them to spin with very little internal friction.


Case 1: If we assume the internal friction to be zero, then the wheels spin freely with respect to the plane, regardless of the plane's velocity. In this case, as the treadmill only contacts the plane at the wheels, and there is no friction to prevent forward motion of the plane, the plane takes off.


Case 2: If the internal friction is so great that the wheels cannot spin at all, the entire contact force propagates through to the plane and acts contrary to the forward motion of the plane. As the laws of physics tell us, the coefficient of static friction (motionless) is greater than the coefficient of kinetic friction (motion). Therefore, the greatest amount of friction occurs when the plane is stationary.

This force is equal to the coefficient of friction, multiplied by the plane's weight.

Case 2a: The force of friction is equal to or greater than the force applied by the plane's engines. The plane cannot generate enough thrust to overcome the friction, and it remains stationary. It does not move.
Note: This situation occurs during a stationary state, and therefore, occurs regardless of the location of the plane. It could be on a runway, and this would still be true.

Case 2b: The force of friction applied to the plane is less than the amount of thrust the engines can exert. Since the plane can overcome the friction, it begins to move forward. As the wheels are locked, they begin to slide across the treadmill. At this instant, the coefficient of friction becomes kinetic, and the force due to friction decreases significantly. Also at this instant, the treadmill matches the plane's speed, but in the opposite direction. This, however, has no effect on the force due to friction applied to the plane, and it is still less than the stationary friction. Since the plane is able to accelerate forward (thrust > friction), it takes off.

Conclusion:

Since there is only one case (Case 2b) where the plane does not take off, and that case is true regardless of the situation of the plane, and planes can take off, we know that Case 2b is not the case.

Therefore, the plane takes off.

didn't read any of that ^ but the plane won't take off. kthxbi.

but what if the plane is on a treadmill????

If a plane tried to land on a treadmill, would it?

unless the plane is locked in place, its engines will push it forward through the air and yes it'll take off regardless of what the floor beneath it is doing

this is all dumb since the plane wont take off... haw haw.

someone needs to build a bigggg treadmill

didn't read any of that ^ but the plane won't take off. kthxbi

dude, go back and read it

what is the relevance of this question, anyways?

ps can we have a poll on this.
pps the plane doesn't take off. kthxbi

last edited by infi at 17:19:13 20/Jul/07

The plane won't take off.
Cause someone will have stolen it's wheels to pave for their drug addiction.

An aeroplane on a treadmill will back off if CHUB pulls a knife on it.

SHUT THE f*** UP MONGIE

gay discussion, ban all above.

Mongies mum on a treadmill... oh who am i kidding that would never happen.

before i was a hand model, i was a teenage treadmill

http://www.barbarygrant.com/Graphics/teal-deer.gif

OH COOL

last edited by mongie at 18:20:00 20/Jul/07

http://users.bigpond.net.au/ritsuko/emoticons/plane-treadmill.gif

hahahah WHOOP IS THE WINNAR!

i agree with teh whoop

when you run on treadmill, do you get wind in your face?? No. Same principle applies to the plane. Take off the plane will not.

Where the hell did my post go ..

http://homepage.powerup.com.au/~boldajis/images/roflbrothel.gif

we need the

http://upload.wikimedia.org/wikipedia/en/c/cf/Mythbusters_title_screen.jpg

when you run on treadmill, do you get wind in your face?? No. Same principle applies to the plane. Take off the plane will not.

I really hope this is a troll, and you're not serious. I've had a long day, my trollbait sensor is on the fritz, but I really hope that was just a troll.

This had to be the single dumbest thing that's ever come up on the net in years.

I'm with Khel..

Will a kite fly if it is above a treadmill ?

will your mum ?

pwnt

if you were on a plane flying just below the sound barrier, if you got flinged out by the treadmill would you break the sound barrier

If a tree fell in the forest, and it killed paveway, would anyone care?

If you keep making lame ass jokes, will you get banned?? and would anyone care.

would anyone care.

would anyone care?

of u were runnning on a tred mil attached to a jetpack facing forward would you move forward?

noobs of course it would take off

lol if clint makes it through puberty, will qgl stop thinking he's a wanker?

DOCTOR KARL SAID ON JJJ THAT THE PLANE WOULD NOT TAKE OFF SO NA NA NA NAAAA.

lol i can't believe there are serious replies in this thread

seriously what the f***

its hilarious because nobody stipulated any conditions on the treadmill and what they are trying to achieve. so basically nobody knows the context yet everyone thinks they have the correct answer. There are situations where the plane will and wont take off depending on what the f*** the point of the argument was in the first place. Mythbusters need to put this one to rest once and for all!!!

But what if the treadmill had a giant f*** off fan in front of it?!?!?!?

But what if the treadmill had a giant f*** off fan in front of it?!?!?!?

Obviously you would now have a space shuttle.

lol parabol

What would Jesus do?

Jesus died on the cross for the answer to the treadmill question.

It's obvious if Jesus was on a treadmill he would take off... that's a no brainer.

The REAL question is, if Moses was on a treadmill in the Red Sea, would it still split?

f*** guys, seriously, If the plane doesnt have any air going over its wings it not gonna take off.

It doesnt matter how fast the treadmill is going or anything, its just not gonna happen and anyone that thinks it will is an idiot.

I think my head just exploded.

Anyone who seriously believes that it wont take off is retarded.

Even if you take in to account friction, if you put a skateboard on the treadmill you would only need to supply enough force to overcome the friction to make it move forward. Moving forward = air speed = lift. Doen't matter how fast the wheels are spinning because they DON'T react the torque back into the mounts. Think about it.

yeah f*** guys seriously
shutup and let viper explain how the treadmill somehow manages to stop airflow over the wings

Someone post this to mythbusters....

it's not gonna take off... it's just not.

I believe it can fly.

Although when I first heard the question I pictured the plane staying in the same spot relative to the ground and slowly floating upwards.

If andre leaves town travalling at 60MPH and the treadmill spins to a speed of 45MPH at what time does the elephant become an opinion.

Of course it is going to take off.

An aeroplane engine is designed to generate force with air, not land. The wheels on a plane are freewheel, and therefore provide no drag on the plane. As the aeroplane engine generates force with the air, the engine will propel the plane through the air. The engines would start to push the plane forward, and the wheels would spin. As the wheels spin, the treadmill would start spinning and speed up to compensate for the speed of the wheels. However, as the treadmill increases speed, so will the wheels to compensate for the speed of the treadmill increasing. The two will continue to get faster and faster to compensate each other increasing, and as this test involves no limits on speed/durability of treadmill/wheels, they will continue to spin faster and faster. However, the engines would continue to generate force with the air, and this force would propel the plane forward at an increasing speed, until such time as it reaches sufficient airspeed to generate lift.

FB

i like the internet

same!

Honest question here..

If you put a running treadmill outside, and run on it really fast, will you get hit by the wind?

Shouldn't you be running, not the treadmill?

its about the relative speeds lolz

If you put a running treadmill outside, and run on it really fast, will you get hit by the wind?

That depends on whether I am standing upwind, and whether I have eaten onions.... :)

Nobody answered my question :(

Do I really have to transport a treadmill outside and test this theory by myself?

If you put a running treadmill outside, and run on it really fast, will you get hit by the wind?

f***ing hell don't do that ... you'll take off!

This must be some kind of funny test some academic made up so they could laugh at stupid people. Stupid people think the plane takes off, smart or really stupid but lucky people think the plane wont. I see the funny, why dont all you other smart people think so too?

edit: I dont think my brain can even begin to comprehend the true extent of the question, let alone answer it so im out.

last edited by qmass at 21:07:08 22/Jul/07

the plane wont take of i discused this with my flight instructor a few years ago. basicly the only thing that would be happening if a plane was on a treadmill would be the wheels turning. to get a plane into the air you need air flow over the wings, on a treadmill there is no airflow over the wings because it is stationary.

the only way this could work is if there was a big f*** off storm with 100k+ winds blowing towards the plane.

ktnxbi end of discussion.

p.s anyone that thinks it will take of never did physics and has never flown a plane

thats just elementary. damn rtards

Do I really have to transport a treadmill outside and test this theory by myself?

Only if you strap fire extinguishers to your arms, turn on the treadmill, flap your arms and make plane noises.. You have to make the noises or else you won't have a chance! (oh and post the video of it on youtube k thx)

can some1 test this already plz

To the people who can't understand why it will take off:

If you had a car on the treadmill, would it move forward?

What most people seem to overlook is the most fundamental thing about this whole problem and that is the ambiguous nature of the question. You can answer both ways when all you ask is "plan on treadmill, plane fly?"

If the plane is on a 5KM long treadmill then it can take off, like has been argued a trillion times by total morons with text book knowledge on friction etc and if its just a dyno-type machine or a treadmill like any treadmill in existance but scaled up for a plane then the plane would just roll off it and crash and go nowhere.

The point is, it is completely f***ing retarded how many 'geniuses' argue out the ability of the plane's wheel bearings, resulting friction, thrust required to generate force to overcome friction and bring in car and cable tied to plane analogies when they overlook a jet engines inability to take air and pull it over the wing.

The argument shouldnt be about whether the aircraft moves, its about whether air moves over the wing and if it does then its not on a treadmill, its taking off down a moving runway and if no air moves over the wing but its flying along at 500KM/H not moving relative to the earth (staying on a treadmill) then it cant get lift, regardless of how fast its moving on the treadmill.

Its like the running on a treadmill vs skateboard holding onto a rope attatched to a wall in front of the treadmill, it doesnt matter where your thrust comes from, if you move like a car or you pull a cable while you sit on a skateboard and roll off the treadmill youve come off the treadmill and even if you keep on running forward and 'fly' then you arent taking off on a treadmill, you just broke free of its fiendish clutches.

p.s anyone that thinks it will take of never did physics and has never flown a plane

Its doing physics that makes people f*** the question up, they needed to do english and not finish physics in high school or first year.

The original question states the treadmill has an infinite length.

pwnt

The original question states the treadmill has an infinite length.

Well f*** me, that is the first time ive ever seen a question state that. I guess under that condition the plane takes off on a moving runway machine and if it hadnt said that it would crash off the treadmill and not take off. Both answers are the same thing and both questions are the same with english deciding whether the plane is taking off or moving off the treadmill and crashing.

Ive seen people argue that the plane will crash and not take off AGAINST people saying the plane will take off because the wheels are not the source of thrust when they both have the same answer they are just arguing the english without knowing it.

im suprised no one has thrown a "car + dyno - is it really going 200k's mang" situation in here yet haha

im suprised no one has thrown a "car + dyno - is it really going 200k's mang" situation in here yet haha

Every time I have heard the question its always been explained like a dyno/treadmill where it was not infinitely long and ive always called the person a c*** for saying it would take off - because taking off on a dyno or a short treadmill implies that the plane didnt move but some how got airspeed and ive always said the s*** cant be getting airspeed if its still on a treadmill... I just read the OP and its the first time the question has been worded properly so I take that back for QGL. On most internet locations when the question is posed and it just says "treadmill" then people are c***s but on QGL people are just too lazy to read the OP, like me. I like to get into the arguing about s*** randomly cause its more fun.

the question is neither unanswerable nor ambiguous

cause we already had this argument and the "plane takes off" people won convincingly, kthxbi

sorry if u weren't there

props to the fake flight instructor testimonial though

wtf do dinosaurs have to do with treadmills.

Everyone knows you need wheels to take off. Noticed how all planes with damaged wheels crash?

Exactly.

last edited by parabol at 22:15:02 22/Jul/07

the plane wont take of i discused this with my flight instructor a few years ago

Please warn me whenever you are in the air so i can not be.

Just use a line of sandbags in front of the treadmill. Problem solved.

sure, if you wanted to cause a massive amount of damage to a plane

Maybe c*** is an arab?

Jet engines are the initial force of the plane, then also AIDED by the planes aerodynamics, INCLUDING the wings. The sheer mass and shape of the plane would require one f***ER of an engine to get it off the ground without the aid of air. If by chance you were able to make the engines run at such a rate, the plane would in theory "fly" off of the ground. NOT because of the air pressure under the wings, but because of the sheer force of the engines. in this way, however, it is not acting like a "plane" and more of a really confused shuttle.

This type of flying (through use of the engines and not the aerodynamics) is also called ROCKET SHIPS.


Possible, but really f***ing stupid.

last edited by Phooks at 22:32:10 22/Jul/07

Just use a line of sandbags in front of the treadmill. Problem solved.

hahaha thats gold. Still dont see how a tank is stopped by these either.

What if the plane is a harrier? Then it would just take off vertically and the discussion would be ended.

It clearly states in the question that the treadmill will automatically run in complete opposite to any movement of the plane.

If this is true then how is the plane ever going to move forward??? If it does move forward then the treadmill is not doing what it states in the question.

and if it doesnt move forward then it doesnt fly.

to move forward the plane would need some kind of novel technique that propels the plane through the air around the plane and not along the ground

haha

tell us more, viper

It clearly states in the question that the treadmill will automatically run in complete opposite to any movement of the plane.

If this is true then how is the plane ever going to move forward??? If it does move forward then the treadmill is not doing what it states in the question.

and if it doesnt move forward then it doesnt fly.

It just means that the wheels spin faster, becuase its the combined speed of the thrust and moving 'treadmill' I still stand by the question being bulls*** unless its worded as precisely as it is in this case, I dont remember it being so clearly outlined in previous iterations though :(

The question needs to state a lot of things that some people here are just taking for granted.

Things like, friction. If we're assuming friction doesn't exist then the plane will take off since the treadmill won't be able to hold the plane still no matter how fast it goes because the plane doesn't rely on its wheels for movement. If friction IS in play, then the treadmill will be able to move backwards at such a speed that will hold the plane stationary and it won't take off.

Things like, friction. If we're assuming friction doesn't exist then the plane will take off since the treadmill won't be able to hold the plane still no matter how fast it goes because the plane doesn't rely on its wheels for movement. If friction IS in play, then the treadmill will be able to move backwards at such a speed that will hold the plane stationary and it won't take off.

Friction coefficients are not high enough. I remember reading somones math on wheels from 1937 applied to a 747's mass and it still wouldnt be enough to counter the thrust of the engines... the wheels would just skid I think was the outcome.

You're all retarded. It takes off. Definitely.

Tested it and it worked.

Also, LOL @ Viper.

It clearly states in the question that the treadmill will automatically run in complete opposite to any movement of the plane.

If this is true then how is the plane ever going to move forward??? If it does move forward then the treadmill is not doing what it states in the question.

and if it doesnt move forward then it doesnt fly.

LOLOOLOL
Did I mention the plane lifts?

PS Like I said before, the first time I heard this question, I pictured a plane hovering over a treadmill. I was thinking "PHWOAR IS IT POSSIBLE?!"

i got ur mum on a treadmill and she took off

o noes

pwnt

hahaha thats gold. Still dont see how a tank is stopped by these either.

You're not old school enough.

If this is true then how is the plane ever going to move forward???

The same way it stays in the air. Big jet engines.

Things like, friction. If we're assuming friction doesn't exist then the plane will take off since the treadmill won't be able to hold the plane still no matter how fast it goes because the plane doesn't rely on its wheels for movement. If friction IS in play, then the treadmill will be able to move backwards at such a speed that will hold the plane stationary and it won't take off.

hehe

those are some strong little heat-resistant wheels you're conjuring up there

Picture a plane landing on a treadmill. It comes down touches down, and will still be moving forward regardless of speed of the treadmill in the opposite direction. Otherwise all the passengers would be skittled to the front of the plane. Thinking from this angle suggests to me that they plane would move forward on the treadmill and eventually take off. The wheels would be spinning like buggery. The wheels on a plane are there to keep it from scraping its belly along the ground and provide less friction for take off, not to give it speed for take off.

to move forward the plane would need some kind of novel technique that propels the plane through the air around the plane and not along the ground

If only there was such a technology, then we could all take off from treadmills... but alas it's not to be.

This stupid f***ing question keeps coming up doesn't it?

If the plane moves forward, the plane can take off. If the plane is held inert relative to ground, then plane can't take off. It depends on how magic the theoretical treadmill and plane are as to whether or not it can move through the air (aka 'fluid'). I guess its possible to fly a plane like a kite if you had a big enough fan in front of it, but thats another stupid question.

NASA as always has the answers:

http://www.grc.nasa.gov/WWW/K-12/airplane/Images/lift1.gif

Lift is the force that directly opposes the weight of an airplane and holds the airplane in the air. Lift is generated by every part of the airplane, but most of the lift on a normal airliner is generated by the wings. Lift is a mechanical aerodynamic force produced by the motion of the airplane through the air.

Lift is generated by the difference in velocity between the solid object and the fluid. There must be motion between the object and the fluid: no motion, no lift. It makes no difference whether the object moves through a static fluid, or the fluid moves past a static solid object.

last edited by Hogfather at 09:48:16 23/Jul/07

Hogfather: too much technical information and not enough speculation/misunderstanding.

Doh, noted for future reference.

Here, have a dragon. And a trolley bar.

Most people understand the concept of lift. The questions is whether the plane can move forward on a treadmill or will it be kept stationary, whether or not the plane will generate lift isnt relevant in this form of the question. Fubar's flight instructor said the same thing as you are saying but its wrong when the treadmill is of infinite length, becuase there will be lift since the plane can accelerate on a treadmill, if the treadmill is short then it will just move off the treadmill and crash and if its long it will take off.

Hence the question is bulls*** because it depends on how its worded. It wont take off but it will move forward off the treadmill that exists, unlike an infinitely long treadmill which wouldnt be a treadmill since treadmills come back and you run over the same bit of belt over and over unlike this magic infinite conveyer belt of plane takeoff with super hot plane wheels.

What I mean is that somone who understands the concept of lift will automatically say the plane wont take off, when the treadmill is explained like a 'real' treadmill because they dont begin to consider whether the plane will move forward on the treadmill, its assumed that the plane magically sits on the treadmill and therefor cannot possibly take off. So you have people arguing about lift when the question is about whether the plane can move forward and speed up, which if it can obviously means lift causes it to fly but its not an argument about whether wind speed = lift its about whether a vehicle with engines that do not power through the wheels but through jet engines will move foward on a treadmill device.

So the question is really about the intepreation of the wording - which is bulls*** becuase english is a waste of time and its all about FMV's

hoggy I don't think any of that is being questioned by anyone, your picture and comments don't do anything to address the people claiming that the treadmill will impede the motion of the plane through the air. So scrap your picture and get another one which shows the wheels just spinning faster and faster while the plan continues to move in the direction it's being thrust despite the best efforts of the treadmill

qmass, you need to get over your mental picture of a treadmill, seriously.

the question isn't bulls*** at all - if you're going to imply the treadmill is likely to only be a certain length so the plan runs off it at some point, why not make a similar assumption and assume the treadmill is a belt around the entire planet so you never run out of surface, yet the belt is of finite length?

hoggy I don't think any of that is being questioned by anyone, your picture and comments don't do anything to address the people claiming that the treadmill will impede the motion of the plane through the air. So scrap your picture and get another one which shows the wheels just spinning faster and faster while the plan continues to move in the direction it's being thrust despite the best efforts of the treadmill

But I like the picture :( It has NASA on it

Becuase the would not be of infinite length, that would be a belt the length of the circumference of the earth, wouldnt it?

All im saying is that: The plane takes off when the question is explained as it is in this thread. When its explained more concisely, people automatically envisage a plane on a normal 'treadmill' and that is why there is such retarded argument on the net. I think that most people are actually in agreement, but focus on the wrong part of the problem.

People act like c***s in the 'will take off' because it seems that people arguing that it wont take off are wrong, when alot would come to the same conclusion as them if they were focusing on whether the plane would move forward. The people that automatically see a normal treadmill (when its not stated explicitely that its infinitely long, that is what I did anyway) assume the plane is being magically held on this treadmill and therefor its not moving forward and wont take off - without actually considering the most important thing which is the whole 'not a car, a plane' thing.

I think its bulls*** becuase when its worded the right way, many more people would agree that it takes off, but it seems like many people like to continue the bulls*** and give people s*** for being wrong, when its more to do with how they interpreted the question, rather than whether they can understand the problem.

Im just talking bulls***, I understand the concept and that the plane takes off and im not focusing on the 'image' of a treadmill... im trying to explain why some people say it wont take off, even though they would otherwise be able to come to the correct conclusion - if the questions is worded differently. In this thread where the question was presented how it is - there are no excuses... but im talking about most of the cases on the net.

Even Dr. Karl (the smartest man in Australia, obviously) said the plane would not take off becuase there is no lift. He did the same thing I did (when I first saw the question it was in a more basic form) which was to not consider what the proper question actually asks, because you automatically envisage a plane just rolling along on a treadmill, rather than starting to take off on a super long runway sized conveyer belt that automatically ajusts its speed to match the speed of the plane. You need that information to actually consider that part of it, which is the most important part theoretically.

edit: I think the easiest way to explain the answer is to just say that the treadmill belt pulls the wheels faster - like when you run you are making the earth spin by under you! :P (that second part is more bulls***, the first isnt)

last edited by qmass at 10:58:34 23/Jul/07

Becuase the would not be of infinite length, that would be a belt the length of the circumference of the earth, wouldnt it?

it'd be of finite length yeah but the point is that you'd never run out of treadmill surface, thus ruling out the issue of coming to the end of the treadmill

I get what you're saying, I think the question isn't meant to be a full on scientific thing though, it's just meant to be more like those conundrums you hear, to get people thinking. It just gets over-analyzed for some reason

I get what you're saying, I think the question isn't meant to be a full on scientific thing though, it's just meant to be more like those conundrums you hear, to get people thinking. It just gets over-analyzed for some reason

EXACTLY! Its like we just argued when we thought the same thing. Its the same thing that happens with this problem, and all of my bulls***, communication is a bitch.

i still didnt read any of the thread but the plane won't take off omgz lol. the wings will clearly hit the handrails.

http://www.upgradetravelbetter.com/wp-content/uploads/2006/12/plane-on-treadmill.jpg

can we have the question amended to reflect the handrails being removed. I can see that cover on the end of the treadmill becoming an issue later too, might pay to give some thought to removing it as well provided it doesn't leave the end of the treadmill exposed to the elements - which reminds me, can this treadmill survive outside anyway?

I agree that the handrails should be removed.

They get in the way of airflow over the wheels.

The question is not will the plane take off.

BUT

Will the plane move forward on a treadmill, regardless of what speed the treadmill surface is moving at. Cos if it can start to move forward it will eventually take off.

The answer in a practical sense is yes, because no treadmill is ever going to get to a speed where it will significantly impact the performance of the wheels.

Why ?

There are few forces that affect a plane in this scenario.
Gravity, duh. But its only effect in this situation is via friction.
The engines. They push forward.
Air friction (only an issue if the plane if moving forward relative to the air, which the freaks who thick it won't take off are saying is 0).
And the friction created via the wheel (this includes tyre to ground, wheel to bearing/hub), which will be the force opposing forward motion. And these things are designed to minimise friction.

I think the tyres would blow long before the friction prevent forward motion (At which point its worth mentioning that the Concorde is designed to take off with all tyres blown). But ok lets assume you have an infinitely powerful treadmill surface that can achieve stupidly insane speeds (hundreds of kms/hour). Then yeah it won't take off. Not to mention that this is going to have to have some insane acceleration.

So in theory its possible. But to ruin the scenario all you have to do is use some higher grade lubricants and some high rated larger diameter tyres.

In reality... no.


Another way to look at it.
You are wearing roller blades on a treadmill, holding a rope fixed to the wall.
You turn on the treadmill holding on to the rope, you aren't moving relative to the ground. Can you pull yourself forward ?
With any luck you slip and fall over and get thrown into a wall and your mate videoing it caught it all and its on youtube for us to laugh at. But yeah of course you will. Now if you have an insanely modded treadmill that can do speeds up to something greater then the maximum speed that the rollerblade wheels can do then yeah you can't, but good luck doing it.

your wrong

also haha @ demon

It just gets over-analyzed for some reason

cause d*******s keep making threads about it

If a airplane is on the surface of a planet that is rotating at 1,670km/h, will it take off?

you made me google for the earth's rotational speed

If a airplane is on the surface of a planet that is rotating at 1,670km/h, will it take off?

More to the point, would the earth spin faster at the poles than the equator? Where is the best location to try this test?

The question is not will the plane take off.

BUT

Will the plane move forward on a treadmill, regardless of what speed the treadmill surface is moving at. Cos if it can start to move forward it will eventually take off.

I agree. It's all about the intended effect of the treadmill on the relative position of the plane to the air around it.

I disagree. I reckon it's all about the intended effect the introduction of the treadmill will have on the individual reading the question.

If a airplane is on the surface of a planet that is rotating at 1,670km/h, will it take off?

If a planet was to spin at that sort of speed, then it wouldn't be able to sustain human life, and therefore it would be very unlikely that an airplane would even be there to take off.

However if the plane did happen to be on this ultra-fast spinning planet, then the only way it could take off is by driving in the same direction as the spin, there's no way a plane could drive 1,670km/h so it couldn't oppose the planets spin.

Answering a theoretical question with another isn't going to win you any nobel prizes.

Not to mention the centripetal force from the spin would overcome gravity and throw the plane into the air if it was spinning that fast... unless of course gravity is strong enough to counter the centripetal force, and in that case it would obviously flatten the airplan with it's strength anyways. Again making your exercise pointless theory.

I wouldn't expect anything else from you.

If a planet was to spin at that sort of speed, then it wouldn't be able to sustain human life, and therefore it would be very unlikely that an airplane would even be there to take off.

we must all be dead then hey?

however i think typo should have also said that the airplane is on the equator.

last edited by ravn0s at 15:00:36 23/Jul/07

reel em in like a sintky

speed is relative. time is a concept. distance is like a relative that has no concept. aeroplanes fly in the air. treadmills are for fat people with nowhere to go. centripetal force is just a bunch of vectors. what was the question again?

what do the handle bars have to do with all this?

speed might be relative to you, but it's not to me

Surely a treadmill is of infinite length anyway

a moving one is - no doubt

0.999~ is equal 1

http://img127.imageshack.us/img127/9265/triangle1os.gif


the plane flies into the empty square

BERMUDA TRIANGLE! LOLO

Any noob can figure out that triangle pic just by looking at it.

Are there langoliers chasing the plane the plane?

The triangle is surprisingly easy to solve but its a cheaky f***er because you automatically start thinking about moving blocks around when you should be looking at the difference in the amount of each square the hypotenues runs through.

The triangle with the gap takes up more room of each square than the one without the gap, that is where the gap area comes from. FIENDISH :P

It wont take off unless the treadmill is blowing air over the wheels!

However if the plane did happen to be on this ultra-fast spinning planet, then the only way it could take off is by driving in the same direction as the spin, there's no way a plane could drive 1,670km/h so it couldn't oppose the planets spin.

no no no. What you do is, you drive the plane in reverse, in the opposite direction to the spin and when you let go, you f***ing sling shot out with the stored kinetic energy, its simple thermodynamics.

then you land on the the asteroid, and you have 8 hours to drill 2 holes to the center and drop the nukes?

last edited by paveway at 17:40:55 23/Jul/07

Im taking my plane to the gym tonight to test this ONCE AND FOR ALL!

Are there model aeroplanes that use the same mechanics as real aircraft?

Someone should try :)

^^ you mean like an RC plane?

I think everyone has had enough of this thread. Feel free to start a new debate on something else.