Somthing to make you think

[SSleepingbeauty]

I had a thought..... If the plane where to fly (which it won't) Could it land on the conveyer belt under the same theory? Would it come to a sudden stop or run off the runway or stop normal?

[drako]

I had a thought.....  If the plane where to fly (which it won't)  Could it land on the conveyer belt under the same theory?  Would it come to a sudden stop or run off the runway or stop normal? 

<{POST_SNAPBACK}>

 

i think it would destroy the conveyor , it comes down with a pretty strong force so it will just do the bouncy thing......unless.......HOW LONG IS THIS CONVEYOR????

[zippy]

For all those who think the plane won't fly because it is not moving I have a question..

 

How fast do the plane wheels (on the treadmill) need to be spinning to create enough rolling resistance to hold back an airplane engine so the plane does not accelerate forward?

 

 

i've already considered that, but that wasn't in the question is the problem. in order to put enough resistance to the wheels to try to push the plane back with equal resistance to the thrusters going forward the wheels would pretty much become powder. unfortunatly, that wasn't how it's worded.

[SSThunder]

plan no fly

[ssfromsd]

I think figuring out the space time continum would be easier for some here, the plan wont fly

[ChevySSandChevy8.1]

Basically saying that the plane is at a stand still as the force of thrust equals the force of friction. The flight of the airplane depends on Bernoulli's principle with the path length of newtonian attack principle of how the deflection of air by the aileron creates lift. IF the plane is essentially standing still because thrust force and friction are equal the air is not moving relative to the wings. Thus the airflow generated by the planing moving at 200-300mph does not occur, the air is not deflected downwards by the air and the coanda effect does not occur. The pressure above the aileron does not become lower than the pressure under the aileron thus Newton's 3rd law is in equilibirium as the pressure above equals pressure below. Thus there is no lift and the plane will not fly. Forces are blanced = no lift. Airflow is required for an airfoil to work.

[Big O]

force of thrust equals the force of friction

 

That would be correct ... but the question states the treadmill is speed matching the airplane ... not that the belt is creating enough friction to counteract the push of the plane.

 

Since the belt speed is just matching plane speed ... the plane will still be pushed forward ... thus creating the necessary lift need to fly.

[Jonmalibuss]

force of thrust equals the force of friction

 

That would be correct ... but the question states the treadmill is speed matching the airplane ... not that the belt is creating enough friction to counteract the push of the plane.

 

Since the belt speed is just matching plane speed ... the plane will still be pushed forward ... thus creating the necessary lift need to fly.

<{POST_SNAPBACK}>

Come on guys think about it the plane has to be movng forward! If it were still or staying in one place what would be causing the tredmill to be moving in the oppostie direction. It clearly states that the treadmill will match the speed of the plane not the wheels. There for the way you guys are thinking of this makes no sence because if I were to go with your theory than the plane could be at WOT sitting still and the treadmill would not be moving because the plane isn't moving! Think about it!

[Banone]

Alright, time for the answer....

 

It will NOT fly----The only way a plane generates lift is by air flow around the wings.... if the belt is keeping the plane stationary there will be no air flow and it wont take off.

<{POST_SNAPBACK}>

I don't know who told you this is the answer but they are wrong. Your answer contradicts itself. "if the belt is keeping the plane stationary" this part is illogical. If the plane is stationary the belt would not move since it matches the speed of the plane. The only way for the belt to move is for the plane to move. If the plane moves it will move through the air which will cause lift under the wings. If it moves forward at 100 miles per hour through the air, it's wheels will be spinning at 200 miles per hour which have no effect on the lift being created under the wings by moving through the air at 100 miles per hour. IT WILL FLY!

[SSThunder]

you guys are over thinking this. The answer has been given already. The plan will not fly. Let's post another question like this. These are fun to debate

[Banone]

I just googled this damn riddle and here is the real answer:

 

December 8th, 2005Airplane on a Conveyor Belt

A riddle was proposed on the Neal Boortz show today:

 

If an airplane is on a large conveyor belt and is trying to take off by exerting the thrust needed to move it forward at 100 knots, and the conveyor belt starts moving backwards at 100 knots, will the plane be able to take off, or will it just sit stationary relative to the ground, with the backwards speed of the conveyor belt counteracting the forward thrust of the plane?

 

Astoundingly, Neal and the rest of his crew took the position that the plane would sit there stationary! Good God… this man is a pilot and has a law degree! I could understand a random high school dropout being fooled by this, but a pilot?

 

Then I googled the riddle, and found a thread on Airliners.net that has been raging on, with the vast majority of people taking Neal’s position… that the plane would not be able to take off.

 

Their argument is this, to quote one poster:

 

Thrust acts accordingly to Newtons Third Law of Motion - every action has an equal and opposite reaction. In the case of an aircraft, the reaction of the engines is that of forward motion, against whatever medium it is stationary. But the ground the aircraft is sitting on in this case is NOT stationary, its providing an exactly CANCELLING force pushing the aircraft back.

 

The problem here, of course, is that the poster (and Neal) cannot disengage themselves from seeing the airplane as a car. The difference between a car and a grounded airplane is that a car uses its wheels to propel itself forward, and an airplane moves itself forward by moving air. They assume that the runway moving backwards would move the plane backwards. This is what would happen with a car (that is in gear), so why not for an airplane? Well, because an airplane’s wheels are free rolling. There is obviously some friction, so there would be some small backwards force, but it would be infinitely small as compared to the forward thrust of the airplane.

 

You can test this with a piece of paper and a matchbox car (which has free rolling wheels like an airplane… or like a car in neutral.) Place the paper on a table, and place the matchbox car on the paper. Take your hand, and hold the car still with a lightly placed finger on top of the car. At this point you are providing no forward thrust, and the “conveyor belt” is not moving. The car remains stationary. Now, continuing to hold the airplane with a lightly placed finger, and start to pull the paper out from under the car, in the backwards direction. According to Neal’s logic, the car should push back on your finger with the same force that you are exerting on the paper… but this is not what will happen. You will find that your lightly placed finger is not stressed to any noticeable extent. The paper will slide out, and the wheels will spin, but the car will not be propelled backwards. The reason for this is is that the rotation of the wheels is not related to the movement of the matchbox car except by the very small friction component of the axle, which your lightly placed finger can easily control.

 

So now we have established that movement of the surface beneath a free wheeling object does not exert a noticeable force on the object. Next, we’ll see what happens when the object is trying to move forward. Attach a string to the matchbox car. Place the car at one end of the paper, and use the string to start pulling the car forward with a steady force. As the car moves forward, start pulling the paper out from under the car, backwards. Do you feel increased resistance as you pull the string? Of course not. The wheels are free rolling! Spinning the wheels does not make the object move!

 

When an airplane takes off, there is one major forward force… the forward thrust. The main rearward force is air resistance. The turning of the wheels provides a small frictional force, but because the wheels are free-rolling, this friction is very small. Unless the wheels are locked, the friction is always going to be less than the thrust, which means that the overall force is still forward, and the plane will still move.

 

Gah… people are freakin’ stupid.

 

Update: There is a variation on this riddle that says that the conveyor belt matches the speed of the plane. It doesn’t matter… the plane still takes off. The conveyor belt could be going 5 times as fast as the plane, and the plane would still take off. You’d get into issues about tires blowing out, but assuming that the wheels can take the strain, the airplane would still take off.

 

Hopefully, this explains it better than I could convey...that pun was intended.

[Big O]

 

:pat on back smiley:

 

And to all the homies rolling with the BIG O on this one

[Buyfire]

with your flux capacitor needle set to "OMFG" you can make anything fly.

[Jonmalibuss]

I just googled this damn riddle and here is the real answer:

 

December 8th, 2005Airplane on a Conveyor Belt

A riddle was proposed on the Neal Boortz show today:

 

If an airplane is on a large conveyor belt and is trying to take off by exerting the thrust needed to move it forward at 100 knots, and the conveyor belt starts moving backwards at 100 knots, will the plane be able to take off, or will it just sit stationary relative to the ground, with the backwards speed of the conveyor belt counteracting the forward thrust of the plane?

 

Astoundingly, Neal and the rest of his crew took the position that the plane would sit there stationary! Good God… this man is a pilot and has a law degree! I could understand a random high school dropout being fooled by this, but a pilot?

 

Then I googled the riddle, and found a thread on Airliners.net that has been raging on, with the vast majority of people taking Neal’s position… that the plane would not be able to take off.

 

Their argument is this, to quote one poster:

 

Thrust acts accordingly to Newtons Third Law of Motion - every action has an equal and opposite reaction. In the case of an aircraft, the reaction of the engines is that of forward motion, against whatever medium it is stationary. But the ground the aircraft is sitting on in this case is NOT stationary, its providing an exactly CANCELLING force pushing the aircraft back.

 

The problem here, of course, is that the poster (and Neal) cannot disengage themselves from seeing the airplane as a car. The difference between a car and a grounded airplane is that a car uses its wheels to propel itself forward, and an airplane moves itself forward by moving air. They assume that the runway moving backwards would move the plane backwards. This is what would happen with a car (that is in gear), so why not for an airplane? Well, because an airplane’s wheels are free rolling. There is obviously some friction, so there would be some small backwards force, but it would be infinitely small as compared to the forward thrust of the airplane.

 

You can test this with a piece of paper and a matchbox car (which has free rolling wheels like an airplane… or like a car in neutral.) Place the paper on a table, and place the matchbox car on the paper. Take your hand, and hold the car still with a lightly placed finger on top of the car. At this point you are providing no forward thrust, and the “conveyor belt” is not moving. The car remains stationary. Now, continuing to hold the airplane with a lightly placed finger, and start to pull the paper out from under the car, in the backwards direction. According to Neal’s logic, the car should push back on your finger with the same force that you are exerting on the paper… but this is not what will happen. You will find that your lightly placed finger is not stressed to any noticeable extent. The paper will slide out, and the wheels will spin, but the car will not be propelled backwards. The reason for this is is that the rotation of the wheels is not related to the movement of the matchbox car except by the very small friction component of the axle, which your lightly placed finger can easily control.

 

So now we have established that movement of the surface beneath a free wheeling object does not exert a noticeable force on the object. Next, we’ll see what happens when the object is trying to move forward. Attach a string to the matchbox car. Place the car at one end of the paper, and use the string to start pulling the car forward with a steady force. As the car moves forward, start pulling the paper out from under the car, backwards. Do you feel increased resistance as you pull the string? Of course not. The wheels are free rolling! Spinning the wheels does not make the object move!

 

When an airplane takes off, there is one major forward force… the forward thrust. The main rearward force is air resistance. The turning of the wheels provides a small frictional force, but because the wheels are free-rolling, this friction is very small. Unless the wheels are locked, the friction is always going to be less than the thrust, which means that the overall force is still forward, and the plane will still move.

 

Gah… people are freakin’ stupid.

 

Update: There is a variation on this riddle that says that the conveyor belt matches the speed of the plane. It doesn’t matter… the plane still takes off. The conveyor belt could be going 5 times as fast as the plane, and the plane would still take off. You’d get into issues about tires blowing out, but assuming that the wheels can take the strain, the airplane would still take off.

 

Hopefully, this explains it better than I could convey...that pun was intended.

<{POST_SNAPBACK}>

There shouldn't be anything to argue about with that explination, it tells you everything you should need to know with this idea and I totally agree with the part that says the conveyor could spin 5 times as fast and it will still take off because it doesn't matter.

[jboyss]

The real question is will the plane move or sit still? The plane would move!The whells on a plane are free spinning ,like the front wheels of a rear wheel drive car.The plane is pushing against the air around the engines not the ground.So regardless of ground speed the engines would still create thurst to make the plane move.When the plane moved fast enough it would create lift and take off.

<{POST_SNAPBACK}>

 

Plan no fly. Thrust moves the plan(which is on wheels). If the movement of the plan is countered by the movement of the treadmill, the plan goes no where. If it doesn't go any where no wind in created to cause the plan to lift off the ground. The plan can move all it wants on the treadmill, but if it doesn't move through the air, then no wind is created. Without wind, the plan can't take off.

 

I like threads like this. It causes my post total to go up LOL

<{POST_SNAPBACK}>

 

 

what in the hell is a plan???