Will it fly?

[md]

Imagine a plane is sitting on a massive conveyor belt, as wide and as long as a runway. The conveyer belt is designed to exactly match the speed of the wheels, moving in the opposite direction. Can the plane take off?

[MihaiG]

im guessing, but as soon as it takes off for that split second, it looses all moving power that is being applied unlike a real plane when you have the engines, so it would probably lift up a few feet or inches and then settle back down.

but i think a better question would be

"will it blend"?

[ericfourfour]

Only if the conveyor belt sends air toward the plane. And it would have to be a lot of air. The plane has to push the air down. If there is no moving air, the plane cannot push it down, and cannot take off.

Or is this a joke?

[syntax_error]

no its simply for a plane to fly it needs lift no?

take you hand stick it out move it across your body that bit of "lift" is there no because of the air movement
now if we some how did the same thing with our hand still however, a large movement below it there still is no change in the air
therefore how can life every be achieved?

Then again its not that simple; since I do not know how well jet engines work for example if they are on and still in on place is there enough air
around it to allow of enough air intake if yes then the above case becomes a fallacy however, if there is not enough air then the above case is bona fide

I think im am right although there may be still fallacies in my syllogistic.

Meh, gave it a try.

[ericfourfour]

Wait, does the plane have propellers or jets? It it does, then yes.

Edit: New idea again, I'm an idiot. If the conveyer belt matches the plane's wheelspeed, there is no displacement, and no moving air relative to the plane.

[syntax_error]

ericfourfour wrote:

Edit: New idea again, I'm an idiot. If the conveyer belt matches the plane's wheelspeed, there is no displacement, and no moving air relative to the plane.

he states:

Quote:

The conveyer belt is designed to exactly match the speed of the wheels, moving in the opposite direction.

[Mazer]

Come on guys.

The belt spins the wheels. That's all.

The wheels aren't running from a motor; they aren't moving the plane forward. All forward motion is coming from the propellers.

[MichaelM]

Ya, Mazer makes a good point. I think it would take off. Besides, imagine that you're running on a conveyer belt that moves backward at the same speed you run forward, would you suggest you couldn't jump off? You could jump, so the plane could fly.

[Mackie]

We can jump if there is lift or not. Maybe a helicopter could take off.

[md]

I am disturbed by the number of people who think it'll happen when flying pigs eat tacos.

[PaulButler]

Assuming the wheel axles are frictionless, there is nothing to stop the plane from moving forward and taking off like normal.

But if there is no friction on the axels, the conveyor belt itself would be a logical impossibility:

code:

Let v = the speed the plane would be traveling at if they conveyor belt were off Let m = the speed of the conveyor belt against the direction of the plane Let w = the speed of the wheels in the direction of the plane We are given m = w. But the speed of the wheels, w = v + m. In other words, if the plane is generating enough thrust to move forward at v m/s, the wheels have to move v m/s more than the belt is moving. (Since the belt does nothing to slow the plane down, if the axles are frictionless). So: if m = w and w = v + m m = v + m v = 0 So if the wheels are frictionless and the plane generates thrust, it is impossible for a conveyor belt to exist where the speed of the conveyor belt matches the speed of the wheels.

Here is another way to think about it:

code:

Imagine you had a wheel with a frictionless axel and you were next to a conveyor belt which would move as fast as the wheel was moving. You stand grounded, but you hold the wheel by the axel and put it on the conveyor belt. Now the conveyor belt could start going at any speed, and the speed would still match the speed of the wheel (since it would cause the wheel to rotate). But suppose you started to push the wheel forward - nothing stops you from doing this, since the axle is frictionless. No matter how fast the belt goes, though, the wheel will always go faster because the wheel is matching the speed of the conveyor, plus it is moving.

[HellblazerX]

Mazer's right. It's the propellers that move the plane forward, not the wheels. Think of those surface-to-air missiles. They don't need wheels to lift off with.

Also, I accidentally voted no, but I meant to vote yes.

[syntax_error]

HellblazerX wrote:

Mazer's right. It's the propellers that move the plane forward, not the wheels. Think of those surface-to-air missiles. They don't need wheels to lift off with.

ya but is there enough air gather-able to move the turbines fast enough
I always thought the plane still needed the wheels for speed to garther air faster and in large amounts
and also the WINGS provide much of the lift as well with the air moving around it no?

EDIT When flying pigs eat tacos! 4 pll said that?? thats as many as yes WoW......sad

[PaulButler]

syntax_error @ Wed Jan 30, 2008 1:57 pm wrote:

HellblazerX wrote:

Mazer's right. It's the propellers that move the plane forward, not the wheels. Think of those surface-to-air missiles. They don't need wheels to lift off with.

ya but is there enough air gather-able to move the turbines fast enough
I always thought the plane still needed the wheels for speed to garther air faster and in large amounts
and also the WINGS provide much of the lift as well with the air moving around it no?

EDIT When flying pigs eat tacos! 4 pll said that?? thats as many as yes WoW......sad

The wheels of a plane are not (usually?) motorized. That's why big planes need to be towed around by trucks on the ground.

[syntax_error]

Quote:

PaulButler wrote:

syntax_error @ Wed Jan 30, 2008 1:57 pm wrote:

HellblazerX wrote:

Mazer's right. It's the propellers that move the plane forward, not the wheels. Think of those surface-to-air missiles. They don't need wheels to lift off with.

ya but is there enough air gather-able to move the turbines fast enough
I always thought the plane still needed the wheels for speed to garther air faster and in large amounts
and also the WINGS provide much of the lift as well with the air moving around it no?

EDIT When flying pigs eat tacos! 4 pll said that?? thats as many as yes WoW......sad

The wheels of a plane are not (usually?) motorized. That's why big planes need to be towed around by trucks on the ground.

yes i do see you point however the problem is still with the forward movement of the plane is not there thus no life by the planes wings
and still the issue : enough air
since the conveyor is moving fast as the wheels the plane is stationary? no?