View Poll Results: what do you think?
Hoss is da man, no
25
33.78%
Geico's question. He knows, yes
42
56.76%
your both wrong its a vto
7
9.46%
Voters: 74. You may not vote on this poll
will the plane fly?
Thats MR Hoss to you buddy!
Joined: Jul 2001
Posts: 2,759
Likes: 3
From: Central Texas
Originally Posted by Geico266
Assuming friction is not part of the problem here. The wheels could be at infinate speed, I could walk up and push the plane and it would move down the conveyor. The speed of the wheels has nothing to do with the thrust of the engine.
Another way to look at it is; the wheels are free rolling, the aircraft is disconnected from any ground influences. (so to speak...) Two aircraft side by side. One on the treadmill scenario and the other on a regular tarmac. Both would accelerate and take off side by side. How fast the wheels are turning wouldn’t matter. Assuming friction is not in the equation the planes would actually take off at the same time.
Another way to look at it is; the wheels are free rolling, the aircraft is disconnected from any ground influences. (so to speak...) Two aircraft side by side. One on the treadmill scenario and the other on a regular tarmac. Both would accelerate and take off side by side. How fast the wheels are turning wouldn’t matter. Assuming friction is not in the equation the planes would actually take off at the same time.
That's the problem. All of the "fly" guys keep trying to pretend that the wheels are not connected to the plane, but they are. If this were a hover craft then it would take off with ease.
Registered User
Joined: Jan 2005
Posts: 914
Likes: 0
From: Waycross, GA
Originally Posted by Hoss
You cannot take friction out of the equation. Also, by your own scenario, the conveyor belt must ALWAYS match the speed of the wheels. Therefore, if you walk up and try to push the plane forward the conveyor belt will speed up to match the wheel speed...and it will go nowhere.
That's the problem. All of the "fly" guys keep trying to pretend that the wheels are not connected to the plane, but they are. If this were a hover craft then it would take off with ease.
That's the problem. All of the "fly" guys keep trying to pretend that the wheels are not connected to the plane, but they are. If this were a hover craft then it would take off with ease.
Exactly Hoss,
The plane is attached to the wheels, the wheels are not driven by the plane, but the plane must sit on them because Isaac Newton said so. GRAVITY.....
Until lift is created, the plane will never take off. The plane will never develop lift, because it will never go anywhere do to the conveyor matching any movement of the wheels. The plane can not move independent of the wheels because gravity is holding the weight of the plane on the wheels.
Thread Starter
Registered User
Joined: Mar 2004
Posts: 3,988
Likes: 7
From: Nebraska
Originally Posted by Hoss
You cannot take friction out of the equation.
Originally Posted by Hoss
Also, by your own scenario, the conveyor belt must ALWAYS match the speed of the wheels. Therefore, if you walk up and try to push the plane forward the conveyor belt will speed up to match the wheel speed...and it will go nowhere.
Registered User
Joined: Dec 2003
Posts: 896
Likes: 0
From: Minnesota
Originally Posted by Hoss
THAT is the key to this riddle. In order for the plane to take off it must travel at TWICE the speed of the conveyor. However, that is not possible because it was stated that the conveyor ALWAYS matches the speed of the wheels no matter how fast they go. Therefore, it is IMPOSSIBLE for the plane to move faster than the conveyor....so the plane will never even MOVE, much less get off the ground.
THAT, gentlemen, is the REAL answer to this little puzzle.
THAT, gentlemen, is the REAL answer to this little puzzle.
looking from the side of the runway on the GROUND, you would see the wheel and the conveyor (im using belt from now on cuz im sick of typing conveyor). if the wheel is going to rotate as it would when the airplane begins forward movement, the wheel would rotate clockwise (assuming you are on the right hand side of the runway and you stay there). that means the belt would match the speed of the wheel (whether that is rotational speed or ground speed
) and in the OPPOSITE DIRECTION OF ROTATION, the belt would be moving counterclockwise. meaning if you are sitting in the plane the runway would look to be coming at you. nowhere in the problem does it say the belt keeps the wheel speed at zero, it just replicates the speed in the OPPOSITE direction of ROTATION. if the wheel is rotating so as to move it towards the end of the runway (the direction of the plane), the belt must be moving towards the back of the runway (or the opposite direction of rotation of the plane's wheel rotation). all this does is spin the wheels faster, not keep them at zero.
and the plane still flies...
Registered User
Joined: Jan 2005
Posts: 914
Likes: 0
From: Waycross, GA
Originally Posted by Geico266
It's my thread!
So the conveyor matches the speed of the wheels? It matches the speed of the WHEELS not the plane. But the speed of the wheels cannot cancel out forward thrust when the thrust is pushing against stationary air.
So the conveyor matches the speed of the wheels? It matches the speed of the WHEELS not the plane. But the speed of the wheels cannot cancel out forward thrust when the thrust is pushing against stationary air.
The speed of the wheels does cancel out forward thrust when there is no lift generated. The thrust has to move the plane forward, which has to be done through the wheels because of gravity. The conveyor will always match the spee of the wheels, but in the opposite direction, so the plane will never actually move. No lift will be created because no air will travel across the wings.
Registered User
Joined: May 2005
Posts: 1,060
Likes: 1
From: Peoria, IL
Originally Posted by pgilles
(whether that is rotational speed or ground speed )
)
Originally Posted by pgilles
BUT the problem states the conveyor ALWAYS matches the speed of the wheels AND in the "OPPOSITE DIRECTION OF ROTATION".
looking from the side of the runway on the GROUND, you would see the wheel and the conveyor (im using belt from now on cuz im sick of typing conveyor). if the wheel is going to rotate as it would when the airplane begins forward movement, the wheel would rotate clockwise (assuming you are on the right hand side of the runway and you stay there). that means the belt would match the speed of the wheel and in the OPPOSITE DIRECTION OF ROTATION, the belt would be moving counterclockwise. meaning if you are sitting in the plane the runway would look to be coming at you.
nowhere in the problem does it say the belt keeps the wheel speed at zero, it just replicates the speed in the OPPOSITE direction of ROTATION. if the wheel is rotating so as to move it towards the end of the runway (the direction of the plane), the belt must be moving towards the back of the runway (or the opposite direction of rotation of the plane's wheel rotation). all this does is spin the wheels faster, not keep them at zero.
and the plane still flies...
looking from the side of the runway on the GROUND, you would see the wheel and the conveyor (im using belt from now on cuz im sick of typing conveyor). if the wheel is going to rotate as it would when the airplane begins forward movement, the wheel would rotate clockwise (assuming you are on the right hand side of the runway and you stay there). that means the belt would match the speed of the wheel and in the OPPOSITE DIRECTION OF ROTATION, the belt would be moving counterclockwise. meaning if you are sitting in the plane the runway would look to be coming at you.
nowhere in the problem does it say the belt keeps the wheel speed at zero, it just replicates the speed in the OPPOSITE direction of ROTATION. if the wheel is rotating so as to move it towards the end of the runway (the direction of the plane), the belt must be moving towards the back of the runway (or the opposite direction of rotation of the plane's wheel rotation). all this does is spin the wheels faster, not keep them at zero.
and the plane still flies...
I think what we really need is to find some common ground - a point on which we all agree - and then go from there.
Thats MR Hoss to you buddy!
Joined: Jul 2001
Posts: 2,759
Likes: 3
From: Central Texas
Originally Posted by Geico266
It's my thread!
Thats MR Hoss to you buddy!
Joined: Jul 2001
Posts: 2,759
Likes: 3
From: Central Texas
Originally Posted by Geico266
But the speed of the wheels cannot cancel out forward thrust when the thrust is pushing against stationary air.
Thats MR Hoss to you buddy!
Joined: Jul 2001
Posts: 2,759
Likes: 3
From: Central Texas
Originally Posted by pgilles
nowhere in the problem does it say the belt keeps the wheel speed at zero, it just replicates the speed in the OPPOSITE direction of ROTATION. if the wheel is rotating so as to move it towards the end of the runway (the direction of the plane), the belt must be moving towards the back of the runway (or the opposite direction of rotation of the plane's wheel rotation). all this does is spin the wheels faster, not keep them at zero.
and the plane still flies...
and the plane still flies...
This plane will do nothing except for sit there with its wheels spinning on the conveyor.