Mythbusters punk'd whole internet

[ConstipatedVigilante]

Originally posted by: spidey07

As the treadmill sped up you had to pull yourself harder and harder just to maintain position.

Well, duh. I suppose no one here ever goes to the gym. If you run on a treadmill, you have to run faster as it speeds up. It's not different for other objects.

 

[LegendKiller]

Originally posted by: spidey07

Originally posted by: Tweak155
Provided a realistic airplane that isn't underpowered and a treadmill / conveyor belt that man can make, anyone with common sense should agree the airplane will take off.

I won't ever disagree that you COULD CREATED a scenario where it wouldn't, but any logical person would agree it isn't realistic.

Again,

Stay in bounds of the original question.

I honestly think this type of question is what separates smart people from others. All kinds of assumptions are made by plane take off folks. The truly smart people, that have a really good grasp of the physics involved can see and mentally and mathematically deduce the problem.

Then again me and my buddies used to ride on a skateboard on a treadmill at max speed and first hand experienced just how much the treadmill can push you back. Real world + experience + advanced physics = plane doesn't take off.

Naturally, the only way scientists every agree to anything is to break it down into simple terms without testing. Either your a fucking moron, or you agree with us. That's such a great way of handling things, I'm glad the scientific process operates this way.

It comes down to it that I am plenty smart and yet I completely disagree with you. That doesn't make me a moron, it just means that neither of us have conclusively proven that this cannot happen (or can). There are plenty of pieces of evidence that this does occur, including the YOuTube video of the plane moving on the treadmill.

What matters, really, is whether the plane has enough thrust to counteract any friction the wheels can cause. Considering that the planes have tens of thousands of pounds and can take off in much shorter distances than they normally do (optimal take offs), it's easy to believe that they can overpower more or less any friction applied.

Considering the engines can counteract any friction *and* they act upon air, not ground, then the reaction of a massive controlled explosion and the opposite reaction of pushing forward, then the plane will take off.

You can go on and on about friction, but in the end, I don't believe it is correct. I am not calling you stupid, or a moron, but you're the one who obviously has the problems with intelligence if that's all you can resort to.

 

[LegendKiller]

Originally posted by: ConstipatedVigilante
A plane's ability to take off is based on the lift it can get under its wings. If it's not moving forward (thus the air moving around the wings) then it can't take off. Right?...

Edit: Some people seem to think that the plane's speed relative to the ground is what's important, but that's not true. Its speed relative to the air around it is what matters. That's how lift works. Now, if you had the plane on said conveyor belt/treadmill with a headwind, then it would take off, but fly backwards. So it would have to be going a bit faster than the treadmill to take off in place in a wind tunnel. I think.

Again, the plane moving forward has everything to do with it sucking air in, compressing it, exploding it, and shoving it at a velocity backwards causes it to move forwards. The force of the treadmill is nothing compared to what the engines generate in forced explosion.

 

[LegendKiller]

Originally posted by: spidey07

Originally posted by: ultimatebob

Originally posted by: spidey07

Originally posted by: Tweak155
Provided a realistic airplane that isn't underpowered and a treadmill / conveyor belt that man can make, anyone with common sense should agree the airplane will take off.

I won't ever disagree that you COULD CREATED a scenario where it wouldn't, but any logical person would agree it isn't realistic.

Again,

Stay in bounds of the original question.

I honestly think this type of question is what separates smart people from others. All kinds of assumptions are made by plane take off folks. The truly smart people, that have a really good grasp of the physics involved can see and mentally and mathematically deduce the problem.

Then again me and my buddies used to ride on a skateboard on a treadmill at max speed and first hand experienced just how much the treadmill can push you back. Real world + experience + advanced physics = plane doesn't take off.

Exactly. I still say that the Mythbusters are going to end up crashing the plane!

Do you know just how hard it is to pull off a kickflip on a treadmill?

Such a simple trick that you can do without thought while rolling. Try it on a treadmill. It's hard. really hard.

To deny the treadmill doesn't push the plane back - I just can't see how people can even believe this. Come up with all kinds of analogies you wish. You can't deny physics.

I know it seems like trolling but we really did spend countless hundreds of hours on a skateboard on a treadmill. What the heck were we gonna do? It was raining.

As the treadmill sped up you had to pull yourself harder and harder just to maintain position.

No kidding, that's because you can't generate enough force. A plane doesn't need to do it for hours, just long enough for it's force to counteract others.

 

[spidey07]

Originally posted by: LegendKiller
No kidding, that's because you can't generate enough force. A plane doesn't need to do it for hours, just long enough for it's force to counteract others.

True, but why do so many seemingly smart people think the treadmill cannot impart this force?

That is what is so mind boggling.

According to the question the treadmill is capable of infinite acceleration.

 

[randay]

Originally posted by: spidey07

Originally posted by: LegendKiller
No kidding, that's because you can't generate enough force. A plane doesn't need to do it for hours, just long enough for it's force to counteract others.

True, but why do so many seemingly smart people think the treadmill cannot impart this force?

That is what is so mind boggling.

According to the question the treadmill is capable of infinite acceleration.

nope, it doesnt say that one way or the other, thats your assumption.

 

[Eeezee]

Originally posted by: spidey07

Originally posted by: LegendKiller
No kidding, that's because you can't generate enough force. A plane doesn't need to do it for hours, just long enough for it's force to counteract others.

True, but why do so many seemingly smart people think the treadmill cannot impart this force?

That is what is so mind boggling.

According to the question the treadmill is capable of infinite acceleration.

Precisely; in other words, the treadmill provides sufficient friction to counteract ANY movement. That's the hypothetical situation. Use a little imagination, people. How do they think Einstein came up with relativity? He sure as hell didn't derive it empirically.

So many people on this forum don't know what a hypothetical situation is. Obviously no treadmill exists that is capable of infinite acceleration. However, if it did, and the plane were placed on top of it, and the treadmill provided enough force to counteract any acceleration provided by the engine, then the plane would not take off.

In the hypothetical situation provided in the plane-treadmill scenario, the plane does not move. The sum of the forces on the plane is equal to zero. What actually generates lift is air moving over/under the wings, and since the plane is not moving the plane will not take off.

If you had a giant fan, however, one that could displace lots of air over the wings of the aircraft, then it would take off (even with the treadmill running).

 

[Eeezee]

Originally posted by: randay

Originally posted by: spidey07

Originally posted by: LegendKiller
No kidding, that's because you can't generate enough force. A plane doesn't need to do it for hours, just long enough for it's force to counteract others.

True, but why do so many seemingly smart people think the treadmill cannot impart this force?

That is what is so mind boggling.

According to the question the treadmill is capable of infinite acceleration.

nope, it doesnt say that one way or the other, thats your assumption.

Maybe the version you read didn't say anything one way or another, but the version I read specified very clearly that the treadmill is capable of putting out unlimited force, but only puts out enough such that the plane does not move forward.

 

[randay]

Originally posted by: Eeezee

Originally posted by: randay

Originally posted by: spidey07

Originally posted by: LegendKiller
No kidding, that's because you can't generate enough force. A plane doesn't need to do it for hours, just long enough for it's force to counteract others.

True, but why do so many seemingly smart people think the treadmill cannot impart this force?

That is what is so mind boggling.

According to the question the treadmill is capable of infinite acceleration.

nope, it doesnt say that one way or the other, thats your assumption.

Maybe the version you read didn't say anything one way or another, but the version I read specified very clearly that the treadmill is capable of putting out unlimited force, but only puts out enough such that the plane does not move forward.

IF it said that, then whats the question exactly? How stupid would it be if after stating all of that, you ask "Can the plane take off?". Its clear that this shit has been going on for so long that nobody even knows what the original question was. It simply says that there is a treadmill that matches the airplanes speed in reverse. then asks if the airplane can take off or not.

 

[Tweak155]

Originally posted by: spidey07

Originally posted by: Tweak155
Provided a realistic airplane that isn't underpowered and a treadmill / conveyor belt that man can make, anyone with common sense should agree the airplane will take off.

I won't ever disagree that you COULD CREATED a scenario where it wouldn't, but any logical person would agree it isn't realistic.

Again,

Stay in bounds of the original question.

I honestly think this type of question is what separates smart people from others. All kinds of assumptions are made by plane take off folks. The truly smart people, that have a really good grasp of the physics involved can see and mentally and mathematically deduce the problem.

Then again me and my buddies used to ride on a skateboard on a treadmill at max speed and first hand experienced just how much the treadmill can push you back. Real world + experience + advanced physics = plane doesn't take off.

First off, I'm not making any assumptions. I'm taking any decently designed airplane (heck, YOU pick) and any man made conveyor belt in mind when answering this. Where does the question specify the airplane model? And, if the conveyor belt keeps the plane going 0 mph, and since the conveyor belt HAS TO MATCH THE SPEED OF THE PLANE, then I guess that means the conveyor belt moves at 0mph... If it keeps the plane still, how does it ever go past 0mph? If the conveyor belt moves faster to keep it at 0mph, plane speed != conveyor belt speed. Oh wait, that is making an assumption? Or is it outlined in the problem? Oh boy, now we gotta move to conveyor belt = wheel speed. Guess what, plane takes off! Gee, lets just picture something LOGICAL. Don't hurt yourself! Imagine a plane on a conveyor belt, yes, it IS that simple! Its funny you need to nit pick the problem in order to get your answer. I could do the same thing.

You are comparing a skateboard to an airplane because they both have wheels? A device that needs traction on its wheels to steer, creating more friction? Let alone the flat wheels and horrible bearings and no engine. My puck will bounce as high as your tennis ball because they are both used in sports... yeah sounds pretty stupid.

If you've ever ridden in an airplane (let alone in a car without a child's seat, I'm really wondering), then you've experienced the airplane uses its ENGINES to slow the plane down for the most part after it lands... not it's wheels on the ground like a skateboard.

Boy what angle is the conveyor belt at? It isn't specified in the problem, guess I'll use whatever interpretation best suits my answer! Or logically assume its flat because it is the only scenario that makes sense...

Its pretty obvious most of the logical people gave up on this thread, I'm probably just more on the stubborn side. Why I waste my time, I cannot tell you. I suppose this is moderately entertaining.

 

[her209]

Originally posted by: Eeezee
Precisely; in other words, the treadmill provides sufficient friction to counteract ANY movement. That's the hypothetical situation.

The maximum amount of frictional force that can be applied by the treadmill to the wheel is precisely, the normal force N multiplied by the coefficient of static friction, us. Any more force and the wheels slip, in which case the amount of frictional force decreases because uk is always less than us. Conversely, if the airplane applies more force than N * us, the plane overcomes the friction between the wheels and treadmill.

To find a:

Ff = N * us = mplane * a

Rewritten and reduced, it comes to:

a = g * us

Easily, any jet engine can generate enough force on a plane such that its acceleration > a, especially a hypothetical one.

 

[Tweak155]

Originally posted by: her209

Originally posted by: Eeezee
Precisely; in other words, the treadmill provides sufficient friction to counteract ANY movement. That's the hypothetical situation.

The maximum amount of friction that can be applied by the treadmill to the wheel is precisely, the normal force N multiplied by the coefficient of static friction, us. Any more force and the wheels slip, in which case the amount of frictional force decreases because uk is always less than us. Conversely, if the airplane applies more force than N x us, the plane overcomes the friction between the wheels and treadmill.

To find a:

Ff = N x us = mplane x a

Rewritten and reduced, it comes to:

a = g x us

Easily, any jet engine can generate enough force on a plane such that its acceleration > a, especially a hypothetical one.

Dude, they don't even understand with simple words. Formulas will just make them have to use bikes instead of skateboards to prove their point.

 

[Eeezee]

Originally posted by: her209

Originally posted by: Eeezee
Precisely; in other words, the treadmill provides sufficient friction to counteract ANY movement. That's the hypothetical situation.

The maximum amount of frictional force that can be applied by the treadmill to the wheel is precisely, the normal force N multiplied by the coefficient of static friction, us. Any more force and the wheels slip, in which case the amount of frictional force decreases because uk is always less than us. Conversely, if the airplane applies more force than N * us, the plane overcomes the friction between the wheels and treadmill.

To find a:

Ff = N * us = mplane * a

Rewritten and reduced, it comes to:

a = g * us

Easily, any jet engine can generate enough force on a plane such that its acceleration > a, especially a hypothetical one.

You are correct, I was under the belief that the treadmill could provide infinite torque to the wheels by moving infinitely quickly, but that is clearly not the case; the maximum torque is determined by the friction between the two surfaces. In physics-land, the plane will take off. In magic treadmill land, where the treadmill can produce as much force upon the plane as it likes (which I believe was the hypothetical situation), the plane will not take off.

I think the more interesting case is truly the infinite-force fan blowing at the plane. It prevents the plane from moving forward, but clearly the plane can still take off.

 

[Eeezee]

Originally posted by: Tweak155
Dude, they don't even understand with simple words. Formulas will just make them have to use bikes instead of skateboards to prove their point.

You're a moron. You need to get over yourself. I'm sure you've never made a mistake in your pathetic little existence.

I (and I'm sure most of ATOT) hope you DIAF

 

[jagec]

Originally posted by: her209

Originally posted by: Eeezee
Precisely; in other words, the treadmill provides sufficient friction to counteract ANY movement. That's the hypothetical situation.

The maximum amount of frictional force that can be applied by the treadmill to the wheel is precisely, the normal force N multiplied by the coefficient of static friction, us. Any more force and the wheels slip, in which case the amount of frictional force decreases because uk is always less than us. Conversely, if the airplane applies more force than N * us, the plane overcomes the friction between the wheels and treadmill.

To find a:

Ff = N * us = mplane * a

Rewritten and reduced, it comes to:

a = g * us

Easily, any jet engine can generate enough force on a plane such that its acceleration > a, especially a hypothetical one.

I did the calculation earlier on. Assuming a 100,000 kg plane (somewhat lighter than a 777), the maximum force that can be generated on the wheels before exceeding their traction is 880kN. The engine packages for the 777 vary from 640 to 1050kN. So you can't say that any jet engine can generate enough force to break the wheels loose.

 

[Tweak155]

Originally posted by: Eeezee

Originally posted by: Tweak155
Dude, they don't even understand with simple words. Formulas will just make them have to use bikes instead of skateboards to prove their point.

You're a moron. You need to get over yourself. I'm sure you've never made a mistake in your pathetic little existence.

I (and I'm sure most of ATOT) hope you DIAF

Wow at least I didn't try to voice my opinion as "most of ATOT"... who is full of them self when they try to speak on the behalf of everyone? And I certainly don't claim authority over anyone's intelligence level.

And I never directly called anyone a moron, I was poking fun at a previous post.

It was a joke. And wasn't even aimed at you. Reminds me about a song about being vain.

That being said, I hope you don't take any of this seriously.

 

[rikadik]

If you really think that the question was whether a plane could take off a treadmill which always applied enough force to keep the plane stationary then I think you have entirely missed the point of the problem.

 

[smack Down]

Originally posted by: randay

Originally posted by: Eeezee

Originally posted by: randay

Originally posted by: spidey07

Originally posted by: LegendKiller
No kidding, that's because you can't generate enough force. A plane doesn't need to do it for hours, just long enough for it's force to counteract others.

True, but why do so many seemingly smart people think the treadmill cannot impart this force?

That is what is so mind boggling.

According to the question the treadmill is capable of infinite acceleration.

nope, it doesnt say that one way or the other, thats your assumption.

Maybe the version you read didn't say anything one way or another, but the version I read specified very clearly that the treadmill is capable of putting out unlimited force, but only puts out enough such that the plane does not move forward.

IF it said that, then whats the question exactly? How stupid would it be if after stating all of that, you ask "Can the plane take off?". Its clear that this shit has been going on for so long that nobody even knows what the original question was. It simply says that there is a treadmill that matches the airplanes speed in reverse. then asks if the airplane can take off or not.

It doesn't need to say that the treadmill is capable of infinite acceleration for it to be capable of infinite acceleration. The treadmill most be capable of infinite acceleration otherwise it can not match the speed of the plane in reverse.

 

[smack Down]

Originally posted by: her209

Originally posted by: Eeezee
Precisely; in other words, the treadmill provides sufficient friction to counteract ANY movement. That's the hypothetical situation.

The maximum amount of frictional force that can be applied by the treadmill to the wheel is precisely, the normal force N multiplied by the coefficient of static friction, us. Any more force and the wheels slip, in which case the amount of frictional force decreases because uk is always less than us. Conversely, if the airplane applies more force than N * us, the plane overcomes the friction between the wheels and treadmill.

To find a:

Ff = N * us = mplane * a

Rewritten and reduced, it comes to:

a = g * us

Easily, any jet engine can generate enough force on a plane such that its acceleration > a, especially a hypothetical one.

Sure but can it generate more then a of a hypothetical treadmill? Do you know what the surface of the treadmill is?

 

[manlymatt83]

Absolute proof is here: here

 

[dug777]

Originally posted by: Tweak155

Originally posted by: Eeezee

Originally posted by: Tweak155
Dude, they don't even understand with simple words. Formulas will just make them have to use bikes instead of skateboards to prove their point.

You're a moron. You need to get over yourself. I'm sure you've never made a mistake in your pathetic little existence.

I (and I'm sure most of ATOT) hope you DIAF

Wow at least I didn't try to voice my opinion as "most of ATOT"... who is full of them self when they try to speak on the behalf of everyone? And I certainly don't claim authority over anyone's intelligence level.

And I never directly called anyone a moron, I was poking fun at a previous post.

It was a joke. And wasn't even aimed at you. Reminds me about a song about being vain.

That being said, I hope you don't take any of this seriously.

You're a complete jerk, Tweak155.

 

[rikadik]

Originally posted by: smack Down
The treadmill most be capable of infinite acceleration otherwise it can not match the speed of the plane in reverse.

Umm...

The treadmill must be capable of the same acceleration as the plane.

Which is not infinite.

So...

What the hell are you talking about?

 

[The Boston Dangler]

http://dsc.discovery.com/video...956&titleId=1347908538

 

[Kev]

Have any of you clowns who think the plane won't take off even heard of a free body diagram?

These plane and treadmill threads make me so angry.

 

[dainthomas]

Originally posted by: Eeezee
So many people on this forum don't know what a hypothetical situation is. Obviously no treadmill exists that is capable of infinite acceleration. However, if it did, and the plane were placed on top of it, and the treadmill provided enough force to counteract any acceleration provided by the engine, then the plane would not take off.

If you have a magical infinite treadmill and normal wheels it will melt the wheel bearings, rip the wheels off, and the plane will crash.

If you have a magical infinite treadmill and magical frictionless wheels, then no force is generated on the fuselage and the plane takes off.

If you have a normal treadmill and normal wheels, the plane takes off.

I honestly can't believe this is still being debated.